NO.PZ2016010802000041
问题如下：
An operator of a ski resort is considering offering price reductions on weekday ski passes. At the normal price of €50 per day, 300 customers are expected to buy passes each weekday. At a discounted price of €40 per day 450 customers are expected to buy passes each weekday. The marginal revenue per customer earned from offering the discounted price is closest to:
选项：
A. €20.
B. €40.
C. €50.
解释：
A is correct.
Marginal revenue per unit is defined as the change in total revenues divided by the change in quantity sold. MR = ΔTR ÷ ΔQ. In this case, change in total revenue per day equals €3,000 [(450 x €40) – (300 x €50)], and change in units sold equals 150 (450 – 300). €3,000 ÷ 150 = €20.
考点：边际收益
解析：
首先求得总收益的增加量€3,000= [(450 x €40) – (300 x €50)]
再求得销售量的增加量150=450 – 300
之后套用公式：边际收益=总收益的增加÷产量的增加
€3,000 ÷ 150 = €20.
这道题可以用mr=p（1-1/｜e｜）求解吗
