【留學】GMAT數(shù)學考試04年1月(三)

58.給出一個柱形圖，橫坐標是六至十二月的平均每日用電量。 縱坐標是千瓦。 每月頭600度電每度$0。14，超過的每度$0。11。 求八月的cost.

59.給出一個柱形圖，橫坐標是working hours,縱坐標是人數(shù)。 求working hours 的median.

60.DS, 不放回抽樣，共有English and Spanish 良種，抽兩本，問抽得at least one english book的概率。

1）english 與spanish 的比是1：3

2）書的總數(shù)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， 有圖， 一底角60度，另一底角45度角， 45度角所隊邊長10,求60度角所隊邊長為多少。

答案： 5根號6

67.某人去商店買東西，1/2買了a, 1/3 for b, 1/10 for c, and the rest $6 for candy. ask the total.

ans: 90