Q3:
At a certain food stand, the price of each apple is ￠ 40 and the price of each orange is ￠ 60. Mary selects a total of 10 apples and oranges from the food stand, and the average (arithmetic mean) price of the 10 pieces of fruit is ￠ 56. How many oranges must Mary put back so that the average price of the pieces of fruit that she keeps is ￠ 52?
A. 1
B. 2
C. 3
D. 4
E. 5
我查過了 好想沒有人問過這一題
請問 答案為什麼是E 不是B呢? | 
