Please try to follow me, as I demonstrate a method of solution.
This could get complicated. I'll try to go slowly, and you must
stop me if I do anything that's not clear.
Ready ?
You said that -5c/8 = 20
Multiply each side by 8: -5c = 160
Divide each side by 5 : - c = 32
Multiply each side by -1 : c = -32
Answer:
5
Step-by-step explanation:
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
I believe the answer is 9.7e-6