Problem:
The average cost of a long-distance call in the USA in was cents per minute, and the average cost of a long-distance call in the USA in was cents per minute. Find the approximate percent decrease in the cost per minute of a longdistance call.
Answer Choices:
A.
B.
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E.
Solution:
The difference in the cost of a long-distance call per minute from to was cents. The percent decrease is .
Answer: .
The problems on this page are the property of the MAA's American Mathematics Competitions