[問題]GWD25-Q23

[evelyn_yeh]

Q23.
At a fruit stand yesterday, the price of each apple was $0.10 more than the price of each orange. What was the total revenue from the sale of oranges at the fruit stand yesterday?
(1) The number of oranges sold at the fruit stand
yesterday was 5 more than the number of
apples.
(2) The total revenue from the sale of apples
at the fruit stand yesterday was $15.00
ans(C)

請問是如何算出的??

[evelyn_yeh]

我的媽咪呀
人緣太差
都沒人理我
還是我的問題太弱智

[chour]

哈~你都考完了吧?
還是來回一下好了,我覺得答案是E
設蘋果售價P,數量Q
橘子售價P-1,數量R
(1)R=Q+5.....不充分
(2)PQ=15.....不充分
一起考慮,求(P-1)R=(P-1)(Q+5)=PQ+5P-Q-5=10+5P-Q
不充分

[chris8888]

根據題目 : 假設orange price = x, apple price = x+0.1

根據一, 假設apple quantity = a, orange quantity = a + 5
x * (a+5) + (x+0.1) * a <== 解不出

根據二, 假設apple quantity =a , (x+0.1) * a = 15, 假設orange quantity = b
15 + b * x =? <== 解不出

(1) + (2),
x * (a+5) + (x+0.1) * a = T (Total Revenue)
15 + x * (a+5) = T (Total Revenue) <== 應該試算不出來, 三個variables, two equations

答案E被推出