58.给出一个柱形图，横坐标是六至十二月的平均每日用电量。 纵坐标是千瓦。 每月头600度电每度$0。14，超过的每度$0。11。 求八月的cost.
59.给出一个柱形图，横坐标是working hours,纵坐标是人数。 求working hours 的median.
60.DS, 不放回抽样，共有English and Spanish 良种，抽两本，问抽得at least one english book的概率。
1)english 与spanish 的比是1：3
2)书的总数少于20本
61.scientist studies the migration trend of a group of geese. The group contains 30% male geese. Among the geese that later on migrated, 20% are male. What is the ratio of migration factor for male geese to the migration facotr for female geese? (migration factor for sex X = number of migrated individual with sex X/total number of individuals with sex X)
Solution: Assume total geese X, of which Y migrated.
The answer is simple [(20%Y)/(30%X)]/[(80%Y)/(70%X)] = ...
62.Some guy has 6 albums of anthology from which he read one poem at least. All peoms in the albums are different. Did he read more than 6 poems from at least one of the album?
a) he has read 22 poems in total.
b) the numbers of poems he read from each album are all distinct.
Anwser: C
63. k, l, m are positive integers, does k has more prime factors than m
a) k = 30l
b) m = 10^k
Answer: C
64.sqrt{2sqrt(63) + 2/[8 + 3sqrt(7)]}
Answer: 4
65.two right cylinders, A and B. radius of A is 2 times radius of B. height of A is half the height of B. If B's radius is x and B's height is y. What is the difference between surface area of A and that of B.
Solution:
A's suface 2*pi*(2x)^2*(y/2) + pi*2*(2x)*(y/2)
B's surface 2*pi*x^2*y + pi*2xy
Difference = A's - B's
66.三角形, 有图, 一底角60度,另一底角45度角, 45度角所队边长10,求60度角所队边长为多少.
答案: 5根号6
67.某人去商店买东西,1/2买了a, 1/3 for b, 1/10 for c, and the rest $6 for candy. ask the total.