Mathematics Middle School

the cost of running an appliance varies jointly as the number of watts used, the hours of operation, and the cost per kilo-watt hour. A 6000 watt convection oven operates for 10 minutes for 15 cents at a cost of 7.5 cents per kilo-watt hour. what is the cost of cooking two meals if each meal takes 70 minutes to make?

Answers

Answer 1
Final answer:

The cost of cooking two 70-minute meals on a 6000-watt appliance with a kilo-watt rate of 7.5 cents will be roughly $1.05.

Explanation:

Your question relates to the calculation of the cost of running an appliance based on its power, time of use, and the cost per kilo-watt hour. When evaluating power and energy consumption, we use an equation for energy, which states that E = Pt, where E is the energy (in kilo-watt hours), P is the power (in kilo-watts), and t is the time (in hours).

First, to find the cost, we need to convert everything to respective units. The 6000 watts is equivalent to 6 kilowatts (kw), and 10 minutes is equivalent to 10/60 or approximately 0.167 hours. The cost per kilo-watt hour is 7.5 cents.

The energy consumed would thus be E = Pt = (6kw)(0.167 hr)= 1kwh. The cost of running the appliance for 10 mins is (1kwh)(7.5 cent/kwh) = 7.5 cents.

To cook one meal, with a time of 70 minutes (or approximately 1.167 hours), we will have E = Pt = (6kw)(1.167 hr)= 7kwh. The cost of cooking one meal therefore would be (7kwh)(7.5 cent/kwh) = 52.5 cents.

Finally, to cook two meals, you would just double this cost, resulting in 2 * 52.5 cents = 105 cents or $1.05.

Learn more about Energy Consumption here:

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Related Questions

Two points move along a circle of length 120m with a constant speed. If they move in different directions, then they meet every 15 seconds. When going in the same direction, one point catches up to the second every 60 seconds. Find the speeds of the points.

Answers

Let x and y be the speeds of the two points. The circle is of length 120m that is Circumference of circle is 120m.When the points are moving in opposite directions, they meet in every 15 seconds.That is the points cover 120m in 15 seconds.As they are moving in opposite directions, so the relative speed will be equal to the sum of speeds of both points.Speed= Distance ÷Time = 120÷15=8m per seconds.

x+y=8

When going in the same direction, one point catches up to the second every 60 seconds.Speed= 120÷60=2 m per seconds

x-y=2.

Solving the two equations by elimination method:

x+y=8.

x-y=2

Adding the equations:

2x=10 ,x=5m / sec.

x+y=8

5+y=8

y=3m/sec.

Thus, the speed of the two points is 5 m/s and 3 m/s.

LAST QUESTION! Please help! Please

Answers

The correct answer is:  [C]:  " 37, 680 mm³ " .
________________________________________________________

Explanation:
________________________________________________________

The formula for the volume, "V" , of a cylinder is:

                →   V  =   [tex] \pi [/tex]  *  r²  *  h  ;  

                           → in which "r = length of radius" ;  "h = height" ;             ________________________________________________________

     {Note that the formula for the volume, "V" , of a cylinder is:
     
                              →   " Base area * height " .
________________________________________________________

         →  Specifically, for a cylinder, the "Base area" is the area of a "circle", because the base is a circle;  

          →  and the formula for the "area of a circle = [tex] \pi [/tex] * r² " ;

          →  in which "r = length of the radius" . 

As such, the formula for the volume, "V" ,  of a cylinder is:
______________________________________________________
       →   Volume  =  (Base area) * (height) ; 

                             =  ( [tex] \pi [/tex] r² ) * h  ;
______________________________________________________

       →   V  =  [tex] \pi [/tex]  r²  h  ; 

                 in which:  "V = volume  {in "cubic units" ;  or, write as " units³ " } ;

                                  "r = radius length" ; 

                                  "h = height" ;
_____________________________________________________
  →  Now, we shall solve for the volume, "V", of the given cylinder in this question/problem:
_____________________________________________________

          →   V  = [tex] \pi [/tex]  r²  h  ; 

                      in which: "r = radius = ? "  ; 

                        →  To find "r" ;  We are given the diameter, "d = 40 mm" ; 
 
                        →  Note that:  "r = d/2 = (40 mm) / 2 = 20 mm " ; 

                              {i.e., "the radius is half of the diameter".}.  

                        →  " r = 20 mm " ;  

                        →  " h = height = 30 mm " {given in figure) ; 
      
                        →  For [tex] \pi [/tex] ; let us use " 3.14 " — which is a commonly used approximation.  

             →  For this question/problem, none of the answer choices are given "in terms of [tex] \pi [/tex] " ;
     →   so we shall use this "numerical value" as an "approximation" ; 
_______________________________________________________

Now, let us plug in our known values into the formula;
     and calculate to find the volume, "V", of our given cylinder; as follows:
_______________________________________________________

    →    V  = [tex] \pi [/tex]  r²  h  ; 

                =  (3.14) * (20 mm)²  * (30 mm) ; 

                =  (3.14) * (20)² *  (mm)²  * (30 mm) ;
          
                =  (3.14) * (20)² * (30) * (mm³) ;

                =  (3.14) * (400) * (30) * (mm³) ; 

                =  37, 680 mm³
__________________________________________________

The volume is:  " 37, 680 mm³  " ;  

          →  which is:  Answer choice  [C]:  " 37, 680 mm³ " .
___________________________________________________
Hope this answer and explanation—albeit lengthy—is of some help to you.
Best wishes!

Section 208 of nassau veterans Memorial Coliseum has 17 rows. The first row has 13 seats in it. If you add two seats to the previous row for each row in the section, how many seats are in row 15? How many seats total are there in the section?

Answers

Row 15 has 41 seats, and the entire section has 493 seats.

We can write the explicit formula for an arithmetic sequence to represent this, since we add 2 each time:

13+2(n-1)

Using 15 for n,
13+2(15-1) = 13+2(14) = 13+28 = 41

To find the total number of seats, we evaluate the sum
[tex]\Sigma_{n=1}^{17} 13+2(n-1)[/tex]

Using technology to evaluate this sum, it is 493.

suppose the probability that a US resident has traveled to Canada is 0.18 to Mexico is 0.09 and to both countries is 0.04 what's the probability that an American chosen at random has travel to either Canada or Mexico

Answers

Canada OR Mexico OR both
0.18 + 0.09 + 0.04 = 0.31

A banquet has charges $750 to feed a large party. Each person must also pay $3.50 for a tip. If divided equally, how many people would need to participate for the cost to be $15 per person

Answers

Let the number of people be x.

Total tips = 3.5x
Total cost = 750
Each person = $15

15x = 750 + 3.5x 
15x - 3.5x = 750
11.5x = 750
x = 65.22

Answer: 66 people should participate.

To of the angles in a triangle measure 57 and 95 degree. What is the measure of the third angle?

Answers

57+95=152

180-152=28

56+95+28=180

Third angle  =28

What is the size of the triangle angles?

Answers

That triangle would be right triangle. :) :)

HAPPY TO HELP

which is an equation of the line that passes through the point (3,-1) and is perpendicular to 2y-3x=7

Answers

Dennis thought of a number. He adds 0.5 to that number and then multiplies the new result by 4. He then subtracts 2 and divides the number by 2. His final answer is 48. What number did Dennis start with?

Barney has a balance of $780 on a credit card with an APR of 31.3%, compounded monthly. About how much will he save in interest over the course of a year if he transfers his balance to a credit card with an APR of 19.1%, compounded monthly? (Assume that Barney will make no payments or new purchases during the year, and ignore any possible late-payment fees.)

Answers

Barney can save
$119.66
in interest over the course of a year if he transfers his balance to a credit
card with an APR of 19.1%, compounded monthly. The correct answer between all
the choices given is the first choice or letter A.

Answer:

Barney will save about $119.66.

Step-by-step explanation:

The compound interest formula is:

A=[tex]p(1+\frac{r}{n})^{nt}[/tex]

Case 1:

when p = 780

r = 0.313

n = 12

t = 1

Putting the values in formula:

[tex]780(1+\frac{0.313}{12})^{12}[/tex]

A = [tex]1.36204\times780=1062.39[/tex]dollars

Interest accured = [tex]1062.39-780=282.39[/tex] dollars

Case 2:

when p = 780

r = 0.191

n = 12

t = 1

Putting the values in formula:

[tex]780(1+\frac{0.191}{12})^{12}[/tex]

A = [tex]1.20863\times780=942.73[/tex]dollars

Interest accured = [tex]942.73-780=162.73[/tex] dollars

Now difference in interest in both cases = [tex]282.39-162.73=119.66[/tex] dollars

Hence, Barney will save about $119.66.

what is the difference between theoretical and experimental probability

Answers

Theoretical probability is what you can calculate without regard to what will happen in the "real world." For example what is the theoretical probability of drawing a red king from a standard deck of cards (no jokers)? It would be 2/52 or 1/26 [The kings would be the king of diamonds and the king of hearts].  That makes absolutely no reference to what would happen in Vegas if you played this simple game for 10 hours.

Before I leave this part of the discussion, there is a computer simulation that mimics this game. It is called the Monte Carlo method. What you do is run a million draws from a computer deck of cards (1 to 52) and draw 1 card. If it is either the King of hearts or the king of diamonds you give yourself 1 point and record that a draw has taken place. If not you just record that a draw has taken place. 

I just ran this simulation and out of a million draws, 38575/1000000 came back as successful. 1/26 = 0.03846 which means that the rounded version was accurate to 3 decimal places. But it was not the same as the theoretical draw.

A real world or experimental probability is like the Monte Carlo method. A survey is another real world or experimental probability. Who would have predicted the results of the last American election? Who would have thought that though Hillary got the popular vote, she was not elected? 

Theoretical: what you calculate.
Experimental: what you get from a sample for example or a survey. Think elections or insurance policies.

there are 450 mangoes and oranges in a fruit stall.There are twice as many mangoes as there are oranges

Answers

equation is 2x (mangoes) + x (oranges) = 450.

2x + x = 450
3x = 450
x = 150

so now we have the amount of oranges= 150

150 * 2 = 300

so oranges = 150, mangoes = 300, and to check our work
150 + 300 = 450
x +2x=450
3x=450
x=450/3
x=150

there are 150 oranges and 300 mangoes

bag of coins contains two quarters 5 dimes 3 nickels and 4 pennies if two coins are randomly chosen from the bag one after the other not replaced and if the total value of the chosen coins is $0.26 what is the probability that a third coin randomly chosen from the back will be a penny

Answers

A - the total value of the first two chosen coins is $0.26
B - third chosen coin is a penny

[tex]P(B|A)=\dfrac{P(A \cap B)}{P(A)}\\\\ |\Omega|=14\cdot13=182\\ |A|=2\cdot4\cdot2!=16\\ |A \cap B|=16\cdot3=48\\\\ P(A \cap B)=\dfrac{48}{182\cdot12}=\dfrac{2}{91}\\ P(A)=\dfrac{16}{182}=\dfrac{8}{91}\\\\ P(B|A)=\dfrac{\dfrac{2}{91}}{\dfrac{8}{91}}=\dfrac{2}{91}\cdot\dfrac{91}{8}=\dfrac{1}{4} [/tex]



How many natural numbers are from 17 to 28?

Answers

12 natural numbers are there
Natural numbers are all the numbers greater than zero so just count the number of numbers there and you will get the answer
Hello there, and thank you for asking your question here on brainly.

Short answer: 11

Why?

Natural numbers are any positive number. How many numbers are inbetween 17 and 28? That would be 11. You can subtract the two numbers to figure that out. {28 - 17 = 11}

Hope this helped you! ♥

A one-tablespoon serving of olive oil contains 120 calories. The label on a bottle of olive oil states that it contains 66 servings. How many calories are in the whole bottle of olive oil?

Answers

I believe the answer is 7920 calories.

The whole bottle of olive oil contains 7920 calories.

To find the total number of calories in the entire bottle of olive oil, one must multiply the number of calories in one serving by the total number of servings in the bottle.  

Given that one tablespoon serving of olive oil contains 120 calories, and the bottle contains 66 servings, the calculation is as follows:

 Total calories in the bottle = Calories per serving [tex]\times[/tex] Number of servings

Total calories in the bottle = 120 calories/serving [tex]\times[/tex] 66 servings

Total calories in the bottle = 7920 calories

Therefore, the whole bottle of olive oil contains 7920 calories.

PLEASE ANSWER CORRECTLY ASAP:

Solve this system of equations:

y = x2 – 3x + 12

y = –2x + 14

Substitute the values of x, –1 and 2, into either original equation to solve for the values of y.

What are the solutions of the system of equations?

One solution is (–1, __ )

The second solution (2, ___)

Answers

first one, subsitute x=-1 for x

[tex]y=(x)^2-3(x)+12[/tex]
[tex]y=(-1)^2-3(-1)+12[/tex]
[tex]y=1+3+12[/tex]
[tex]y=16[/tex]
so one solution is (-1,16)


2nd one, subsitute 2 for x

[tex]y=(x)^2-3(x)+12[/tex]
[tex]y=(2)^2-3(2)+12[/tex]
[tex]y=4-6+12[/tex]
[tex]y=10[/tex]
the second soltuion is (2,10)



so one solution is (-1,16)
the second solution is (2,10)

Answer:

3

Step-by-step explanation:

give brainliest

2. What is similar about the primary structure of each protein?

Answers

The primary structure is held together by peptide bonds that are made during the process of protein biosynthesis.

what is the value of -36/5 (10/9-5/6)

Answers

The value of this equation is -2
The answer is -2 you just multiply and then subtract so it's negative two

25 POINTS SOMEONE HELP ME OUT WITH THIS PLEASEEEE BRAINLIEST ANSWER

Answers

1. [tex]y=7x-1[/tex]

2. [tex]y=3x+b[/tex]
    Sub (1, -5) into equation to find 'b'
   [tex]-5=3(1)+b[/tex]
   [tex]-8=b[/tex]

   [tex]y=3x-8[/tex] 

3. [tex]x=-7[/tex]

4. [tex]y=4[/tex]

A plumber charges $100 to come to a house and $95 dollars per hour that he is there. If the total cost of the plumber’s visit to a house was $385, how many hours was the plumber working at the house?

Answers

3 hours.

First, you have to subtract 100 from 385 to find the total cost of hours at the house. Then, since he charges $95 every hour, you have to divide 385/95 and you get 3 as your answer. Hope this helped :) .

Simplify the expression 1/√(1-cos^2 x) . Remember cos x= 1/csc x

Answers

First, we are going to use the Pythagorean identity: [tex]sin^2(x)+cos^2(x)=1[/tex] to rewrite our expression. Solving for [tex]sin^2(x)[/tex] in our Pythagorean identity  we get that [tex]sin^2(x)=1-cos^2(x)[/tex], so we can rewrite our expression as follows:
[tex] \frac{1}{ \sqrt{1-cos^2(x)} } = \frac{1}{ \sqrt{sin^2(x)} } = \frac{1}{sin(x)} [/tex]

Next, we are going to use the trig identity: [tex]csc(x)= \frac{1}{sin(x)} [/tex] to completely simplify our expression:
[tex] \frac{1}{sin(x)} =csc(x)[/tex]

We can conclude that [tex] \frac{1}{ \sqrt{1-cos^2(x)} }=csc(x)[/tex]

the rate of 4 shirts for $32.00

Answers

the answer is $8

hope this helps
Hey there!

The rate is 8 or $8 for each shirt.

Hope this helps! :)

EXPLAIN AND NO ONE SENTENCE ANSWER

Answers

Draw a line from K to M. If you draw any angle whose vertex is on the upper side of KM, you get two angles that add to 180o. One of the angles is 104x + 1.

But ...

What do you do about the arc? It is 211o - 1? That value = the central angle. A central angle is the angle going from K to the center of the circle to M. 1/2 that amount is the angle going to anywhere on the arc of the circle. So that is 1/2 of 211 - 1 = 105.5x - 1/2

These two angles when added together = 180o

105.5x - 1/2 +  104x + 1 = 180o         Collect like terms on the left
209.5x  + 1/2  =  180                          Subtract 1/2 from both sides
209.5x = 180 - 1/2
209.5x = 179.5                                   Divide by 209.5
x = 179.5 / 209.5
x = 0.8568

<KLM = 104*0.8568 + 1
<KLM = 89.1 + 1
<KLM = 90.1o <<<<< answer




PLEASE HELP WITH #10

Answers

The variable r represents radius. The distance around the circle, if laid into a straight line, is 3 times as long, but has about 0.14 units left. The second power exponent tells us that the circle has two dimensions, not three like a sphere. I hope I answered your question, because some of it was cut off.

When two computers are working together, they can finish updating software in 9 minutes. How long would they take individually to update the software if one computer takes 24 minutes longer than the other?

Answers

First computer takes x min. For 1 min it does 1/x part of work.

Second computer takes (x+24) min. For one min it does 1/(x+24) part of work.

Both computers for one min do   (1/x+1/(x+24)) part of work.

At the same time, both computers for one min do 1/9 part of work.

[tex] \frac{1}{x} + \frac{1}{x+24} = \frac{1}{9} \\ \\ \frac{x+24+x}{x(x+24)} = \frac{1}{9} \\ \\9(2x+24)=x^{2} +24x \\ \\ 18x+216=x^{2} +24x \\ \\ x^{2}+6x-216=0 \\ \\ D=b^{2}-4ac=36+4*216 = 900 \\ \\ x= \frac{-b+/- \sqrt{D} }{2a} = \frac{-6+/-30}{2} \\ \\ x_{1}=-18, x_{2}=12 We can use only positive number here. So, for the first computer x=12 min, for second computer x+24=12+24= 36 min Answer 12 min and 36 min.[/tex]


It would take the computers 12 minutes and 36 minutes respectively to individually update the software

What is an equation?

An equation is an expression that shows the relationship between two or more numbers and variables.

Let t represent the time it takes the fastest computer. Hence:

[tex](\frac{1}{t}+\frac{1}{t+24})9=1\\ \\ t=12 \ minutes[/tex]

It would take the computers 12 minutes and 36 minutes (12 + 24) respectively to individually update the software

Find out more on equation at: https://brainly.com/question/2972832

which of the following values are zeroes for the function below? select all that apply. g(x)=(x^2+4x-12)(x-3)

Answers

what are your answer choices?

answer and explanation:

g(x)=(x^2+4x-12)(x-3)

(x+6)(x-2)(x-3)

x+6=0

-6 -6

x= -6

~~~~~~~~~~~~~~~~~~~

x-2=0

+2 +2

x=2

~~~~~~~~~~~~~~~~~~~

x-3=0

+3 +3

x=3

~~~~~~~~~~

answer: -6, 2, 3.

please help me how do u write in y intercept form a line that goes through (0,2) , (4,1) with a slope of -2??

Answers

Use the point slope form equation: y - y1 = m(x - x1)

(0, 2), (4, 1); m = -2
Plug the numbers in. I will use (0, 2).

y - 2 = -2(x - 0)
y - 2 = -2x 
y = -2x + 2

Please contact me if you have further questions.

A function has the rule y = -2x + 11. Which of the following ordered pairs represents an input of 4 and its output?
(4, 3.5)
(4, 3)
(3, 4)
(3.5, 4)

Answers

The answer is...

(4,3)

Hope this helps!!! :)

-Jared

Which fraction is multiple of 1/10

Answers

2/20 thats one i got for now

Final answer:

A multiple of 1/10 is any fraction obtained by multiplying 1/10 by an integer. For example, 1/10 multiplied by 2 is 2/10, which simplifies to 1/5. Dividing by powers of 10 shifts the decimal point left, making 1.9436 divided by 1,000 equal to 0.0019436.

Explanation:

In mathematics, when identifying a multiple of a fraction, you look for fractions that can be created by multiplying the original fraction by an integer. In the case of 1/10, a multiple would be any fraction where 1/10 is multiplied by a whole number.

For instance:

1/10 multiplied by 2 is 2/10, which simplifies to 1/5 - thus 1/5 is a multiple of 1/10.1/10 multiplied by 3 is 3/10 - hence, 3/10 is a multiple of 1/10.

Multiplying 1.9436 by powers of 10 shifts the decimal point accordingly:

1.9436 × 10 = 19.4361.9436 × 100 = 194.361.9436 × 1,000 = 1,943.6

Conversely, dividing by powers of 10 will shift the decimal point to the left, making the number smaller:

1.9436 ÷ 10 = 0.194361.9436 ÷ 100 = 0.0194361.9436 ÷ 1,000 = 0.0019436

The fraction 15 can be simplified by dividing both the numerator and the denominator by the greatest common factor, in this case, 15, yielding a value of 1.

How do you subtract mixed numbers

Answers

You arrange it like you would a regular number(numerator and denominator , or let me show you rather eh?

     8 5/6          8   15/18
-             =      -                 =  6  7/18
     2 4/9          2    8/18


So your answer is 6 and 7 over 18 


       

Okay first you need to change the fractions into an improper fraction. So 8 5/6 become 53/6 ( multiply 6 and 8 then add 5), and 2 4/9 becomes 22/9(multiply 9 and 2 then add 4). Next you need to find a common denominator that 6 and 9 can go into which is 18. So you multiply the improper fractions by numbers that will make your denominator 18. Multiply 53 and 6 by 3 , and multiply 22 and 9 by 2. Your new fractions should be 159/18 and 44/18. Then you subtract the numerators and keep the denominator the same. The answer is 115/18. You can convert it back to a mixed number if you want. - Nae

how to tell if an ordered pair is a solution to a function

Answers

A) yes
B) yes
C) no

For each of these, substitute the value of x in the ordered pair into x in the function.

For A, x = -5; -5<2, so the piece of the function we want is f(x) = 3.  In our ordered pair, y=f(x)=3, so yes, it is a solution.

For B, x = 2; 2≤2<6, so the piece of the function we want is f(x) = -x+1.  In our ordered pair, y=f(x)=-1; -2+1=-1, so yes, it is a solution.

For C, x = 8; 8≥6, so the piece of the function we want is f(x) = x.  In our ordered pair, y=f(x)=-7; -7≠8, so no, it is not a solution.
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