85/5 = 17
17x3 = 51
17x2 = 34
51:34
for 15 cups of popcorn kernels, oil used = 5 cups
so, for for 27 cups of popcorn kernels, oil used = (5/15)* 27 cups
= 9 cups of oil
<h3>
Answer: 25% decrease</h3>
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Work Shown:
A = old value = 360
B = new value = 270
C = percent change
C = (B-A)/A
C = (270-360)/360
C = -90/360
C = -0.25
C = -25%
The negative C value indicates we have a percent decrease.
Note how 25% of 360 = 0.25*360 = 90, meaning that the price has dropped by 90 galleons. And also note that 360-270 = 90 is that same figure of 90. This helps confirm the answer.
A vertical translation is where is is translated up and down
