129. 4-4平方分之一 (我的第一题白痴题^^")
SA: 15/16
129.
129题可能是GWD13-8
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
The answer is E
130. DS:一串数列求标准差:
(1)最大数等于平均数
(2)range为零
SA:D 大家帮我确认一下
131. 一个卫星绕木星 卫星离木星的地心5800哩 卫星离木星的表面3700哩
求木星圆周长?
SA:4200 PAI
132. 又是委员会问题^^:
a有五人 b有四人 c有三人
ab个各取两人 c取一人的取法有几种??
SA: 180
133.DS:
xy+z=z, Ix-yI>0? x-y的绝对值是否大于零
1. x不=0
2. y=0
SA:A
134. x^2-6xy+9y^2-14=0
求(x-3y)^4=?
SA:196
135.DS:两数中间是否包含0?
1.两数之和<0
2.两数之积<0
SA:B
136 DS:-71.x<0
2.x>-6
SA:C
137.一线段有ABCDEFG 两点之间都是等距
F是3^11...G是3^12
求哪一点是-(3^12) ? (数字没错..但点忘记了) 答案应该是D点
SA:
F=3^11，G=3^12 ==〉d=G-F=2*3^11，即每个点之间的距离
==〉E=F-d=-3^11
==〉D=E-d=-3^11-2*3^11=-3*3^11=-3^12
所以是D点