再问~~~输血 jj 316题

loveborne

316  DS: x,y,z的算术平均数
1）中数=5
2）2y=x+z
我选的是C，为什么呢？因为2）可以得出y是中数，如果y最小，2y<x+z, y最大,2y>x+z。所以这道题不是选E.

之前有人给的条件1是中位数，如果给的是中位数的话，是求不出来呀。。。。

loveborne

287  问x，y，z平均数是 ？
条件一：中位数是3
条件二：2y=x+y
选E

mecsid

弱弱的问。。中数跟中位数什么区别。。。。

gongchenglu

DS三角形ABC，过B点做AC边上的高BH，问角ABC是多少度？(有图)
  (1)BH=AC
  (2)角A=30度

这道题到底选什么啊？拜托帮帮忙

loveborne

A吧

arthur7997

DS三角形ABC，过B点做AC边上的高BH，问角ABC是多少度？(有图)
  (1)BH=AC
  (2)角A=30度

I think the answer should be C. when BH=AC, that means B is a point on the line which is parallel to AC, and distance b/w two lanes is BH (also AC).  Combined with (2), you can only locate one point on the line B, which makes angle BAC = 30, and at same time , angle ABC is confirmed.

yzg1236

中数就是中位数，median

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正确：
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发表于: 4小时8分钟前 - IP:*.*.*.*

只看该用户 大 中 小 #5
DS三角形ABC，过B点做AC边上的高BH，问角ABC是多少度？(有图)
 (1)BH=AC
 (2)角A=30度



I think the answer should be C. when BH=AC, that means B is a point on the line which is parallel to AC, and distance b/w two lanes is BH (also AC).  Combined with (2), you can only locate one point on the line B, which makes angle BAC = 30, and at same time , angle ABC is confirmed.