Question

Jose and Jayden go to the movie theater and purchase refreshments for their friends. Jose spends a total of $43.25 on 5 bags of popcorn and 4 drinks. Jayden spends a total of $24.25 on 3 bags of popcorn and 2 drinks. Write a system of equations that can be used to find the price of one bag of popcorn and the price of one drink. Using these equations, determine and state the price of a bag of popcorn, to the nearest cent.

Answer 1

Answer: The equations are as follows;

5p + 4d = 43.25 ————(1) and

3p + 2d = 24.25 ————(2)

Also a bag of popcorn costs $5.25

Step-by-step explanation: We start by assigning letters to the unknown variables. Let a bag of popcorn be p and let one drink be d. The clues given in the question include the cost of buying five bags of popcorn and four drinks which is a total of $43.25. This can be expressed as

5p + 4d = 43.25 ————(1)

Another clue is that three bags of popcorn and two drinks cost $24.25. This also can be expressed as

3p + 2d = 24.25 ————(2)

Now we have a pair of simultaneous equations as follows

5p + 4d = 43.25 ————(1)

3p + 2d = 24.25 ————(2)

We shall use the elimination method since all the unknowns have coefficients greater than 1. Multiply equation one by 3, and multiply equation two by 5 (so as to eliminate ‘p’)

5p + 4d = 43.25 ——— x3

3p + 2d = 24.25 ——— x5

15p + 12d = 129.75 ———(3)

15p + 10d = 121.25 ———(4)

Subtract equation (4) from equation (3) and we have

2d = 8.5

Divide both sides of the equation by 2

d = 4.25.

That means each drink costs $4.25

We can now substitute for the value of d into equation (2)

3p + 2d = 24.25

When d = 4.25

3p + 2(4.25) = 24.25

3p + 8.5 = 24.25

Subtract 8.5 from both sides of the equation

3p = 15.75

Divide both sides of the equation by 3

p = 5.25. This means a bag of popcorn costs $5.25