(OG) 10th PS Q240

[sencerio]

The organizers of a fair projected a 25 percent increase in attendance this year over that of last year, but attendance this year actually decreased by 20 percent. What percent of the projected attendance was the actual attendance?

(A)45%
(B)56%
(C)64%
(D)75%
(E)80%

答案是c…怎麼看、怎麼想都實在想不通= =lll
麻煩高手解答一下
謝謝

[StanleyHuang]

假設 去年的 attendance 為 a
actual attendance = (1-0.2)a=0.8a
projected attendance = 1.25a
0.8a / 1.25a = 0.64 = 64%

[sencerio]

喔喔，感謝回答