GWD12 几题请教一下

woodruff1

12

Q12:

What was the percent increase in the average (arithmetic mean) contribution per member of a certain public radio station from 1985 to 1995 ?

(1) Total contributions by members increased from $505,210 in 1985 to $1,225,890 in 1995.

(2) The number of members exactly doubled from 1985 to 1995.

答案C，我E。C是什么意思啊？~~~~~

13.

4³ + 4³ + 4³ + 4³ =

A. 4³

B. 4⁶

C. 4⁸

D. 4⁹

E. 4¹²

^{答案错了吧~~~~~A要改成4方：）}

Q24:

y

INE>INE> l

INE>INE>

–

–

2 –

1 –

INE>INE> ا ا ا ا ا ا ا ا x

– 1

–

–

–

The graph of which of the following equations is a straight line that is parallel to line l in the figure above?

A. 3y – 2x = 0

B. 3y + 2x = 0

C. 3y + 2x = 6

D. 2y – 3x = 6

E. 2y + 3x = -6

不好意思不会贴图，大家看一下吧，应该也没答案

怎么这份题目会错这么多？是不是GWD自己出的啊~~~？

himba

12.E
问的百分比。设85年的人n，95年的人2n。
（95人均－85人均）/85人均。其中n可以约掉。
24.A
不觉得A有问题啊。k相同。

elites

Q12

设85年人数为m，95年为2m

total contributions / the number of members = average contribution

所以（1225890/2m－50210/m）/50210/m 即可求出增长的百分比了，

所以我选C，不明白为什么选E。

(1)+(2)