Noticing that there is a pattern of repetition in the question (the numbers are repeated twice), we are assuming that the mean number of words per minute is 88, the standard deviation is of 14 WPM, as well as the number of sixth graders is 137, and that there is a need to estimate the probability that the sample mean would be greater than 89.87.
Answer:
"The probability that the sample mean would be greater than 89.87 WPM" is about [tex] \\ P(z>1.56) = 0.0594[/tex].
Step-by-step explanation:
This is a problem of the distribution of sample means. Roughly speaking, we have the probability distribution of samples obtained from the same population. Each sample mean is an estimation of the population mean, and we know that this distribution behaves normally for samples sizes equal or greater than 30 [tex] \\ n \geq 30[/tex]. Mathematically
[tex] \\ \overline{X} \sim N(\mu, \frac{\sigma}{\sqrt{n}})[/tex] [1]
In words, the latter distribution has a mean that equals the population mean, and a standard deviation that also equals the population standard deviation divided by the square root of the sample size.
Moreover, we know that the variable Z follows a normal standard distribution, i.e., a normal distribution that has a population mean [tex] \\ \mu = 0[/tex] and a population standard deviation [tex] \\ \sigma = 1[/tex].
[tex] \\ Z = \frac{\overline{X} - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex] [2]
From the question, we know that
The population mean is [tex] \\ \mu = 88[/tex] WPMThe population standard deviation is [tex] \\ \sigma = 14[/tex] WPMWe also know the size of the sample for this case: [tex] \\ n = 137[/tex] sixth graders.
We need to estimate the probability that a sample mean being greater than [tex] \\ \overline{X} = 89.87[/tex] WPM in the distribution of sample means. We can use the formula [2] to find this question.
The probability that the sample mean would be greater than 89.87 WPM
[tex] \\ Z = \frac{\overline{X} - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]
[tex] \\ Z = \frac{89.87 - 88}{\frac{14}{\sqrt{137}}}[/tex]
[tex] \\ Z = \frac{1.87}{\frac{14}{\sqrt{137}}}[/tex]
[tex] \\ Z = 1.5634 \approx 1.56[/tex]
This is a standardized value and it tells us that the sample with mean 89.87 is 1.56 standard deviations above the mean of the sampling distribution.
We can consult the probability of P(z<1.56) in any cumulative standard normal table available in Statistics books or on the Internet. Of course, this probability is the same that [tex] \\ P(\overline{X} < 89.87)[/tex]. Then
[tex] \\ P(z<1.56) = 0.94062 \approx 0.9406[/tex]
However, we are looking for P(z>1.56), which is the complement probability of the previous probability. Therefore
[tex] \\ P(z>1.56) = 1 - P(z<1.56) = 1 - 0.9406[/tex]
[tex] \\ P(z>1.56) = P(\overline{X}>89.87) = 0.0594[/tex]
Thus, "The probability that the sample mean would be greater than 89.87 WPM" is about [tex] \\ P(z>1.56) = 0.0594[/tex].
Solve the system by the substitution method.
7x + 8y = -22
3x - y = 26
Select the correct choice below and, if necessary, fill in the answer box to complete your choice.
O A. The solution set is { } (Type an ordered pair.)
O B. There are infinitely many solutions.
O C. There is no solution.
Answer:
A) The solution set is (6,-8).
Step-by-step explanation:
3x - y = 26
-3x - 3x Subtract 3x from both sides
-y = -3x + 26 Divide both sides by -1
y = 3x - 26
Now plug this into 7x + 8y = -22 to solve for x
7x + 8(3x - 26) = -22 Distribute
7x + 24x - 208 = -22 Combine like terms
31x - 208 = -22
+ 208 + 208 Add 208 to both sides
31x = 186 Divide both sides by 31
x = 6
Plug this into y = 3x - 26 to solve for y
y = 3(6) - 26 Multiply
y = 18 - 26 Subtract
y = -8
If this answer is correct, please make me Brainliest!
Final answer:
The system of equations is solved using the substitution method, resulting in x = 6 and y = -8. Hence, the correct choice is the ordered pair (6, -8).
Explanation:
To solve the system of equations by the substitution method, let's start by solving the second equation for y:
3x - y = 26
=> y = 3x - 26.
Now, substitute this expression for y into the first equation:
7x + 8(3x - 26) = -22
=> 7x + 24x - 208 = -22
=> 31x = 186
=> x = 6.
Now, substitute x back into the expression we found for y:
y = 3(6) - 26
=> y = 18 - 26
=> y = -8.
The solution to the system is the ordered pair (6, -8), which means the correct choice is:
O A. The solution set is { (6, -8) } (Type an ordered pair.)
A biologist is studying the effects that applying insecticide to a fruit farm has on the local bat population. She collects 23 bats and finds the mean weight of this sample to be 503.4 grams. Assuming the selected bats are a random sample, she concludes that because the sample mean is an unbiased estimator of the population mean, the mean weight of bats in the population is also 503.4 grams. Explain why this is an incorrect interpretation of an unbiased estimator.
Answer:
The insufficient or relatively small size of the random sample does not guarantee the unbiasedness of the sample mean in any statistical study.Step-by-step explanation:
In Statistics,if the sample mean is an unbiased estimator of population mean,then the expected value of the sample mean is equal or identical to the actual population mean.As the researcher increases the size of the random sample in any statistical study or research, the sample mean increasingly approaches the actual population mean and hence, with increasing sample size with relation to the actual population of the study,the sample mean will become an unbiased estimator of the population mean.In this instance, the biologist has selected only 23 bats for the concerned study which might not be enough considering the entire or actual local bat population. Therefore, even a random sampling of 23 bats will not necessarily ensure that the sample mean will be an unbiased estimator of the population mean, in this case. Hence, the biologist would have to increase the size of the random sample to establish the unbiasedness of the sample estimate or the mean.A large online video game tournament begins with 65,53665,536 teams. The number of teams, t,t, remaining after each round, r,r, can be expressed as t=65,536(12)r.t=65,536(12)r. Eight teams will advance to the quarterfinals. The number of rounds necessary for there to be 88 teams left can be modeled as r=log(1k)log(12).r=log(1k)log(12). What is the value of k?k?
Answer:
k=8192
Step-by-step explanation:
The number of teams,t remaining after each round, r, can be expressed as:
[tex]t=65,536(\frac{1}{2})^r[/tex]
8 Teams will advance to the quarterfinals.First, we determine the round,r at which there will be 8 teams left.
[tex]t=65,536(\frac{1}{2})^r\\8=65536*0.5^r\\0.5^r=8 \div 65536\\2^{-1r}=2^{-13}\\-r=-13\\r=13[/tex]
Using this value of r
[tex]If \: r=\frac{Log\frac{1}{k}}{Log\frac{1}{2}} \\Since\: r=13\\13=\frac{Log\frac{1}{k}}{Log\frac{1}{2}}\\$Cross Multiply$\\Log\frac{1}{k}=13 X Log 0.5\\ $Using a Log b=Log $b^{a}\\Log\frac{1}{k}= Log 0.5^{13}\\\frac{1}{k}=0.5^{13}\\\frac{1}{k}=\frac{1}{8192}\\k=8192[/tex]
of 100 students, 32 are taking Calculus, 29 are taking French, and 13 are taking both Calculus and French, if a student is picked at random
what is the probability that the student is taking Calculus or French?
(Reduce fraction to lowest form)
Step-by-step explanation:
The total number of students = 100
Let A represents calculus and B represents French
The no of students taking calculus = 32
The no of students taking French = 29
The no of students taking calculus and french = 13
the probability that the student is taking Calculus or French = ?
P (AUB) = P(A) + P(B) - P(A∩B)
= [tex]\frac{32}{100}[/tex] + [tex]\frac{29}{100}[/tex] - [tex]\frac{13}{100}[/tex]
= [tex]\frac{48}{100}[/tex]
Reducing to lowest fraction, it becomes [tex]\frac{12}{25}[/tex]
The probability that the student is taking Calculus or French = [tex]\frac{12}{25}[/tex]
The probability that a randomly selected student is taking Calculus or French is 12/25.
To find the probability that a randomly picked student is taking either Calculus or French, we use the principles of set theory, specifically the formula for the union of two sets:
P(A ∪ B) = P(A) + P(B) - P(A ∩ B)
Here,
A = Students taking Calculus = 32
B = Students taking French = 29
A ∩ B = Students taking both Calculus and French = 13
Total students = 100
The formulas for the probabilities are:
P(A) = 32/100
P(B) = 29/100
P(A ∩ B) = 13/100
Now substitute these values into the union formula:
P(Calculus or French) = 32/100 + 29/100 - 13/100 = 48/100 = 12/25
Therefore, the probability that a randomly picked student is taking either Calculus or French is 12/25.
An equilateral triangle is similar to a scalene triangle. True or False
Answer:
False.
Step-by-step explanation:
All the sides of an equilateral triangle are equal.
None of the sides of a scalene triangle are equal to each other.
Therefore, an equilateral triangle is not similar to a scalene triangle.
4. Use a proportion to find the length of the missing side in the following similar figures. (1 point)
10 cm
22 cm
x= 28 cm
x= 30.8 cm
x= 6.4 cm
X = 19 cm
Answer:
x = 19cm
Step-by-step explanation:
use pythagorean theorem:
a² - c² = b²
10² - 22² = b²
100 - 484 = b²
384 = b²
√384 = b
19cm = b or x
Answer:
30.8cm
Step-by-step explanation:
i am from connexus 8th grd pre algrabra
unit 5 lesson 3
1. 1:2
2. C. yes they are similar they have porportional side lengths and = ange measures
3. x = 4.5m
4. x = 30.8cm
5. x = 6 m
i hope this helps! = ) <3
Which statement is true about the graphs of the two lines y =-4/5x+
2 and y=-5/4x-1/2?
The slopes are the only thing we care about when it comes to determining if the lines are parallel or perpendicular. The y intercepts do not affect the answer, so we can ignore them entirely.
The slopes of the two given equations are -4/5 and -5/4. Note how they are both negative. This means that we do not have perpendicular lines. One slope must be positive and the other negative, for perpendicular lines to form.
Another way to see it: the two slopes must multiply to -1 to have perpendicular lines form. We see that (-4/5)*(-5/4) = 1 instead.
Yet another way to see it: The term "opposite reciprocals" means we flip the fraction and we flip the sign (from positive to negative). The reciprocal part happens, but the sign change does not happen.
The lines are not parallel because the slopes would have to be equal for that to happen.
Explain how you could use 25% of a number to find the number
Answer:
you know 25% is one fourth of 100%, aka the whole number, so just multiply the 25% of the number times 4 to get the whole number
Which mathematical terms originated from the Arabic mathematician, al-Khwarizmi
Answer:
algorithm
Step-by-step explanation:
It sounds like algorithm.
The mathematical terms that originated from the Arabic mathematician, al-Khwarizmi, are ""algorithm"" and ""algebra.""
Al-Khwarizmi was a Persian mathematician and astronomer who lived in the 8th and 9th centuries. His works were instrumental in the development of algebra and the use of Hindu-Arabic numerals. The term ""algorithm"" is derived from a Latinization of his name, Algoritmi, and originally referred to the numerical methods he described in his treatise on arithmetic.
The word ""algebra"" comes from the Arabic word ""al-jabr,"" which appears in the title of his book ""Kitab al-Jabr wa-l-Muqabala"" (The Compendious Book on Calculation by Completion and Balancing). This book laid the foundations for algebra as a branch of mathematics, and the terms he introduced are still in use today to describe mathematical procedures and the study of equations and algebraic structures.
A 13 ft ladder leaning against a building touches the building exactly 12 feet above the ground. How far is the building is the base of the ladder round to the nearest hundredth foot
............................
How would you do this question?
2/3 a = 8
castel invests $7178 in a savings account with monthly compounding. after 7 years, the balance reaches $12,543.00. What is the interest rate of the account?
Answer:
r = 129.1 %
Step-by-step explanation:
Using the compounding formula:
A = P (1 + r/t)^nt
$12, 543 = $7178 (1 + r/12)^12(7)
-7178
$5365 = (1 + r/12)^84
[tex]\sqrt[84]{5365}[/tex] = [tex]\sqrt[84]{(1 +\frac{r}{12})^{84}}[/tex]
1.107642572 = 1 + r/12
(0.108 = r/12) (12)
r = 1.2917 = 129.1 %
An initial population of 7 chipmunks in Mary's yard increases by 6% each year. If the function f(x) = abx models this situation, what is the population of the chipmunks in 5 years? (to the nearest whole number)
Answer: there would be 9 chipmunks after 5 years.
Step-by-step explanation:
An initial population of 7 chipmunks in Mary's yard increases by 6% each year. It means that the population is increasing in an exponential rate.
The function that models the situation is expressed as
f(x) = ab^x
Where
a represents the initial population of chipmunks
b represent the rate of growth
x represent the number of years
From the information given,
a = 7
b = 1 + 6% = 1 + 6/100 = 1.06
x = 5 years
After 5 years,
f(5) = 7 × 1.06^5
f(5) = 9
The distance from a ship to two lighthouses on the shore are 4 miles and 7 miles respectively. If the angle between the two lines of sight is 45, find the distance between the lighthouses
Answer:
5 miles
Step-by-step explanation:
In the diagram, the distance between the lighthouse is |AB|=c.
Using Cosine Rule,
c²=a²+b²-2abCos C
=7²+4²-2(4)(7)Cos 45°
=49+16-56cos45°
=25.40
c=√25.40=5.04 miles
The distance between the lighthouses is approximately 5 miles.
Answer:
The distance between the two lighthouse is 5miles
Step-by-step explanation:
Since the shape of the sketch is a right angled triangle we use SOHCAHTOA to solve. An image showing the step by step working is attached.
Suppose that a coin is tossed three times and the side showing face up on each toss is noted. Suppose also that on each toss heads and tails are equally likely. Let HHT indicate the outcome heads on the first two tosses and tails on the third, THT the outcome tails on the first and third tosses and heads on the second, and so forth. (a) Using set-roster notation, list the eight elements in the sample space whose outcomes are all the possible head-tail sequences obtained in the three tosses.
Answer:
S={HHH,HHT,HTH,HTT,THH,THT,TTH,TTT}
Step-by-step explanation:
As can be seen in the Sample Tree attached, the eight elements in the sample space whose outcomes are all the possible head-tail sequences obtained in the three tosses are:
S={HHH,HHT,HTH,HTT,THH,THT,TTH,TTT}
When tossing a coin three times, there are 8 possible outcomes listed as HHH, HHT, HTH, HTT, THH, THT, TTH, and TTT. These elements represent all possible head-tail sequences for three coin tosses.
When a coin is tossed three times, each outcome is a sequence of heads (H) and tails (T). Since there are two possible outcomes for each toss, the total number of possible sequences is 23 = 8. Let's list these sequences using set-roster notation.
The sample space is:
HHHHHTHTHHTTTHHTHTTTHTTTThese elements cover all possible outcomes where each toss can either result in heads or tails.
x = 2, y = 8
The variables x and y vary directly. Use the given values to write an equation that relates x and y
A can of cat food has a diameter of 8 cm. Which measurement is the best estimate for the circumference of the cat food inside the can?
Answer:
ok The circumference of a circle is 2πr or πD if diameter is given.
The answer is 25.13 cm
Step-by-step explanation:
Now method 1:
C=2πr
So finding for radius in this equation=diameter/2
8/2=4 cm
So now 2 × 22/7 × 4
176/7=25.13 cm
OR
C=πD
22/7 × 8
176/7=25.13 cm
A sample of salary offers (in thousands of dollars) given to management majors is: 48, 51, 46, 52, 47, 48, 47, 50, 51, and 59. Using this data to obtain a 95 percent confidence interval resulted in an interval from 47.19 to 52.61. True or False: The confidence interval obtained is valid only if the distribution of the population of salary offers is normal.
Answer:
Step-by-step explanation:
number of samples, n = 10
Mean = (48 + 51 + 46 + 52 + 47 + 48 + 47 + 50 + 51 + 59)/10 = 49.9
Standard deviation = √(summation(x - mean)/n
Summation(x - mean) = (48 - 49.9)^2 + (51 - 49.9)^2 + (46 - 49.9)^2+ (52 - 49.9)^2 + (47 - 49.9)^2 + (48 - 49.9)^2 + (47 - 49.9)^2 + (50 - 49.9)^2 + (51 - 49.9)^2 + (59- 49.9)^2 = 128.9
Standard deviation = √128.9/10 = 3.59
Confidence interval is written in the form,
(Sample mean - margin of error, sample mean + margin of error)
The sample mean, x is the point estimate for the population mean.
Margin of error = z × s/√n
Where
s = sample standard deviation
From the information given, the population standard deviation is unknown and the sample size is small, hence, we would use the t distribution to find the z score
In order to use the t distribution, we would determine the degree of freedom, df for the sample.
df = n - 1 = 10 - 1 = 9
Since confidence level = 95% = 0.95, α = 1 - CL = 1 – 0.95 = 0.05
α/2 = 0.05/2 = 0.025
the area to the right of z0.025 is 0.025 and the area to the left of z0.025 is 1 - 0.025 = 0.975
Looking at the t distribution table,
z = 2.262
Margin of error = 2.262 × 3.59/√10
= 2.57
the lower limit of this confidence interval is
49.9 - 2.57 = 47.33
the lower limit of this confidence interval is
49.9 + 2.57 = 52.47
So it is false
(20 points)
Which number can be multiplied with a rational number to illustrate that the product of
two rational numbers is rational
Answer:
The answer would be B) -2 1/8
Step-by-step explanation: i just took the test and i got that right
Answer:
B) -2⅛
Step-by-step explanation:
All other options are irrational
Which of the following shows the extraneous solution to the logarithmic equation below? log Subscript 3 Baseline (18 x cubed) minus log Subscript 3 Baseline (2 x) = log Subscript 3 Baseline 144
The extraneous solution of the logarithmic problem log₃( 18x³) -log(2x) = log₃144 is -4.
What is Logarithm?A log function is a way to find how much a number must be raised in order to get the desired number.
[tex]a^c = b[/tex] can be written as,
log[tex]_a[/tex]b = c
where a is the base to which the power is to be raised,
b is the desired number that we want when power is to be raised,
c is the power that must be raised to a to get b.
Solving the function using the basic logarithmic value, we get,
log₃( 18x³) -log(2x) = log₃144
log₃ (18x³/2x) = log₃144
log(9x²) = log₃144
Take antilog.
9x² = 144
x = ±4
If we solve further we will get that the value of x can be either -4 or 4, if take the value of x as -4, in the beginning then you will get log₃(18(-4)³) as the log of negative value which is impossible.
Hence, x=-4 is an extraneous solution for the given expression log₃( 18x³) -log(2x) = log₃144.
Learn more about Logarithms:
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You have a drawer with five pairs of white socks, three pairs of black socks, and one pair of red socks. You choose one pair of socks at random each morning, starting on Monday. You do not put the socks you choose back in the drawer. Find the probability of each event. 3. You select black socks on Monday and white socks on Tuesday.
Answer:
20.8%
Step-by-step explanation:
To find the final probability, two separate events must be done and the final propagation is the multiplication of these, like this:
First event:
Probability of black socks on Monday:
Total pair of socks: 1 + 3 + 5 = 9
Number of black socks on Monday: 3
Thus:
3/9 = 1/3
Second event:
Probability of white socks on Tuesday:
Total pair of socks: 8
Number of white socks on Tuesday: 5
Thus:
5/8
Final probability:
1/3 * 5/8 = 5/24
P = 0.208
So the probability would be 20.8%
The probability of black socks on Monday = 1/3
The probability of white socks on Tuesday = 5/8
The calculation for probability:To find the final probability, two separate events must be done and the final propagation is the multiplication of these, like this:
First event:
Probability of black socks on Monday:
Total pair of socks: 1 + 3 + 5 = 9
Number of black socks on Monday: 3
Thus:
Probability will be: 3/9 = 1/3
Second event:
Probability of white socks on Tuesday:
Total pair of socks: 8
Number of white socks on Tuesday: 5
Thus:
Probability will be: 5/8
Final probability:
1/3 * 5/8 = 5/24
P = 0.208
So, the probability would be 20.8%.
Find more information about Probability here:
brainly.com/question/24756209
Water drains very slowly from the nearly level ground in the Gulf Prairies and Marshes ecoregion of Texas. How does the slow movement of water impact the ecoregion?
A. Sediment carried in the water causes significant physical weathering.
B. The water increases the amount of sediment eroded by wind.
C. Sediment carried in the slowly moving water is deposited.
D. The slowly moving water erodes sediment.
Answer:
The correct option is;
C. Sediment carried in the slowly moving water is deposited.
Step-by-step explanation:
Here we note that the drainage rate of the water is slow and the plane of the drainage is given as level ground.
Therefore, there would less mass transport of sedimentary materials from the region and the level planes with slow drainage would favor the deposition of sediments along the level plane
From the above, the correct option is C.
Answer:
C
Step-by-step explanation:
after graphing 4x-2y=5 and y=x, in how many points do they intersect
Answer:
1 at (2.5, 2.5)
Step-by-step explanation:
you can try graphing it on desmo
How does the mean absolute deviation (MAD) of the data in set 1 compare to the mean absolute deviation of the data in set 2?
Set 1: 82, 80, 90
Set 2: 82, 80, 60, 90
1 The MAD of set 1 is 6 less than the MAD of set 2.
2 The MAD of set 1 is 5 less than the MAD of set 2.
3 The MAD of set 1 is 5 more than the MAD of set 2.
4 The MAD of set 1 is 6 more than the MAD of set 2.
Answer:
The MAD of set 1 is 5 less than the MAD of set 2.
Step-by-step explanation:
Kala earns 41 dollars each week working part-time at a bookstore. She earns one additional dollar for each book that she sells.
Let A be the amount (in dollars) that Kala earns in a week if she sells B books.
Write an equation relating A to B. Then use this equation to find the amount of money Kala earns if she sells 14 books.
Equation:
Amount Kala earns if she sells 14 books: dollars
Answer:
A = 41+B
A = 55
Step-by-step explanation:
A be the amount (in dollars) that Kala earns in a week
B = books sold
Kala earns 41 dollars each week working part-time at a bookstore. This does not depend on selling any books
She earns 1 dollar for each book sold
A = 41+B*1
A = 41+B
Let B = 14
A = 41+14
A = 55
Answer:
Equation: A = 41 + B
Amount Kala earns if she sells 14 books: 55 dollars
Step-by-step explanation:
A = 41 + B
B = 14
A = 41 + 14
A = 55
Which statement is true of a rectangle that has an area of 4x^2 +39x-10 square units and a width of (x+10) units
Answer: ( C ) The perimeter of the rectangle is (10x+18) Units
Step-by-step explanation: This is the right answer because I just checked and I did the math
Answer:
it is c i had the same problem
Step-by-step explanation:
Can someone please help
Answer:
x= 52°Step-by-step explanation:
x+90°+33°+165°+20°=360° (complete angle)
x+ 308°=360°
x= 360°-308°
x= 52°
Answer:
x=52
Step-by-step explanation:
So what you would want to do is add up all of the angle measurements given. This give you 308. Now you take this number (308) and subtract it from 360, to give you the answer of 52.
Tom's stockbroker offers an investment that is compounded continuously at an annual interest rate of 3.7%. If Tom wants a return of $25,000, how long will Tom's investment need to be if he puts $8000 initially? Give the exact solution in symbolic form and then estimate the answer to the tenth of a year.
Answer:
It'll take 38.3 years to obtain the desired return of $25,000.
Step-by-step explanation:
In order to solve a continuosly coumponded interest question we need to apply the correct formula that is given bellow:
M = C*e^(r*t)
Where M is the final value, C is the initial value, r is the interest rate and t is the time at which the money was applied. Since he wants an return of $25,000 his final value must be the sum of the initial value with the desired return. So we have:
(25000 + 8000) = 8000*e^(0.037*t)
33000 = 8000*e^(0.037*t)
e^(0.037*t) = 33000/8000
e^(0.037*t) = 4.125
ln[e^(0.037*t)] = ln(4.125)
t = ln(4.125)/(0.037)
t = 1.4171/0.037 = 38.2991
t = 38.3 years
if 3a-2b=8 and a+3b=7 what is the value of 4a+b
Answer:
Step-by-step explanation:
If a + 3b = 7, subtract 3b from both sides of the equation
-3b = -3b then you get
a = 7-3b now plug this into the other equation: 3a-2b=8
3(7-3b) - 2b = 8
21 - 9b - 2b = 8
21 - 11b = 8 add 11 b to both sides
+ 11b +11b
21 = 8 + 11b subtract 8 from both sides
-8 -8
13 = 11b
What is 4a+b?
4(7-3b) + b =
(28 - 12b) + b =
28-11b (from above 13=11b)
28 - 13 = 15
A Broadway theater has 400 seats, divided into orchestra main, and balcony seating. Orchestra seats sell for $70, main seats for $45, and balcony seats for $35. If all the seats are sold, the gross revenue to the theatre is $18,800. If all the main and balcony seats are sold , but only half the orchestra seats are sold, the gross revenue is $16,000. How many are there of each kind of seat.
Answer:
-80 orchestra seats
-200 main seats
- 120 balcony seats
Step-by-step explanation:
Let x b number of orchestra seats
Let y be number of main seats
Let z be number of balcony seats.
Thus, we have the following equations;
For all seats sold;
70x + 45y + 35y = 18,800 - - - - eq1
For half of orchestra sold;
70•½•x + 45y + 35y = 16,000 - - eq2
For total seats;
x + y + z = 400 - - - - eq3
Solving eq1, eq2 and eq3 simultaneously, we have;
x = 80
y = 200
z = 120
Thus, we have;
-80 orchestra seats
-200 main seats
- 120 balcony seats