求助问题

braveMBA

GWD 3 2真题

On Saturday morning, Mallachi will begin a camping vacation and he will return home at the end of the first day on which it rains. If on the first three days of the vacation the probability of rain on each day is 0.2, what is the probability that Malachi will return home at the end of the day on the following Monday?

Key 0.128 第四天下雨和前面几天有什么关系？？ 怎么算出来的。实在想不通。

3 each of the 45 boxes on shelf J weighs less than each of the 44 boxes on shelf k. What is the median wight of the 89 boxes on these shelves?

1) The heavist box on shelf J weights 15 pounds.

2) The lightest box on shelf K weights 20 pounds.

36题

If M is the least common multiple of 90,196 and 300, which of following is not a factor of M?

A 600 B 700 C 2,100 D 900 E 4,900

KEY A

我将90 196 和300 的最小公倍数找出来，然后将其因式分解，然后再把选项因式分解， 然后看选项是否是最小公倍数的因数，可怎么也不可能是600？？

谢谢

daoying

GWD 3 2真题
On Saturday morning, Mallachi will begin a camping vacation and he will return home at the end of the first day on which it rains. If on the first three days of the vacation the probability of rain on each day is 0.2, what is the probability that Malachi will return home at the end of the day on the following Monday?
Key 0.128 第四天下雨和前面几天有什么关系？？ 怎么算出来的。实在想不通。

周一回来，说明周六、周日没下雨，周一下雨。

所以概率为0.8*0.8*0.2＝0.128

3 each of the 45 boxes on shelf J weighs less than each of the 44 boxes on shelf k. What is the median wight of the 89 boxes on these shelves?
1) The heavist box on shelf J weights 15 pounds.
2) The lightest box on shelf K weights 20 pounds.

中数为第（89+1）/2＝45个，所以是J里面最重的。

选A

36题
If M is the least common multiple of 90,196 and 300, which of following is not a factor of M?
A 600 B 700 C 2,100 D 900 E 4,900
KEY A
我将90 196 和300 的最小公倍数找出来，然后将其因式分解，然后再把选项因式分解， 然后看选项是否是最小公倍数的因数，可怎么也不可能是600？？

因为得不到600，所以选600

BTW：如果时间来得及的话建议看看费费详解版。