Question

The cost of 4 cookies, 6 doughnuts, and 3 boxes of doughnut holes is $8.15. The cost of 2 cookies, 3 doughnuts, and 4 boxes of doughnuts holes is $7.20. What is the cost of a box of doughnut holes?

Answer 1

Answer:

$1.25

Step-by-step explanation:

This can best be determined using a set of linear equations that are solved simultaneously.

This pair of linear equations may be solved simultaneously by using the elimination method. This will involve ensuring that the coefficient of one of the unknown variables is the same in both equations.

Let the cost of a cookie be c, cost of a doughnut be d and that of a box of doughnut hole be h then if cost of 4 cookies, 6 doughnuts, and 3 boxes of doughnut holes is $8.15, we have

4a + 6d + 3h = 8.15

and the cost of 2 cookies, 3 doughnuts, and 4 boxes of doughnuts holes is $7.20 then

2a + 3d + 4h = 7.20

Dividing the first by 2

2a + 3d + 1.5h = 4.075

subtracting from the second equation

2.5h = 3.125

h = 1.25

The cost of a box of doughnut holes is $1.25