[求助]求教一道TPrep中的数学题~急~

fjm710

 

stock	number of shares
V	68
W	112
X	56
Y	94
Z	45

the table shows the number of shares of each of the 5 stocks owned by Mr.Sami. If Mr.Sami was to sell 20 shares of stock X and buy 24 shares of stock Y, what would be the increase in the range of the numbers of shares of the 5 shares owned by Mr.Sami?

A.4

B.6

C.9

D.15

E.20

bisakiki

答案是D吗？

fjm710

是的！！！请问怎么作呢？拜托讲详细一点～谢谢～

albert2008

这都不会做，回家看定义去。idiot

gps4145

在没有买卖以前range是112-45=67， 买卖后range是118-36=82. 所以increase range是82-67=15

Apple258

sell 20 shares of stocks x,then x is 36;and buy 24 shares of stocks y ,then y is 118

the new 5 stocks are:68 112 36 118 45.    range（2）=118-36=82

origin range（1）=112-5=67   SO range(2)-range(1)=82-67=15

Apple258

origin(1)=112-45=67

不好意思，漏了个数字，呵呵~

4楼的同学不要这样，大家都是来学习的，共同进步啊~加油`