[問題]考古題Form19 sec3 PS-Q15

[凱薩琳]

Sixty percent of the total number of units a certain product were sold under a brand name and the remaining units were sold undera generic name. The price of each brand-name unit was 75 percent granter than the price of each generic-name unit. Approximately what percent of the total amount spent by consumers on this product was spent for the brand-name units?

(A)5%
(B)30%
(C)45%
(D)65%
(E)70%

Ans:E

[StanleyHuang]

假設共有 T 個 product，然後沒牌子的平價品賣 P 元
(1) 有牌子的全賣掉可得 0.6*T*1.75*P = 1.05*T*P 元
(2) 沒牌子的全賣掉可得 0.4*T*P = 0.4*T*P 元
所求 = (1) / ((1)+(2)) = 1.05/1.45 = 0.72 所以選 (E)

[凱薩琳]

謝謝..我懂了