Question

Question: A box of chocolates contains square chocolates, which weigh 10 g each, and round chocolates, which weigh 8 g each. The combined weight of all the chocolates is 210 g. The number of round chocolates is 3 less than twice the number of square chocolates. Write a pair of linear equations to represent the information given above. Be sure to state what the variables represent. Solve the pair of equations to find the number of square chocolates. Show your work.

Answer 1

Answer: the box contained 9 square chocolates and 15 round chocolates.

Step-by-step explanation:

Let x represent the number of square chocolates contained in the box.

Let y represent the number of round chocolates contained in the box.

The box of chocolates contains square chocolates, which weigh 10g each and round chocolates which weigh 8g each. The combined weight of all the chocolates is 210g. It means that

10x + 8y = 210- - - - - - - - - - -1

The number of round chocolates is 3 less than twice the number of square chocolates. It means that

y = 2x - 3

Substituting y = 2x - 3 into equation 1, it becomes

10x + 8(2x - 3) = 210

10x + 16x - 24 = 210

26x = 210 + 24

26x = 234

x = 234/26

x = 9

y = 2x - 3 = 2 × 9 - 3

y = 18 - 3

y = 15