请教一道问题，谢谢大家！

A certain quantity is measured on two different scales, the R-scale and the S-scale, that are related linearly.  Measurements on the R-scale of 6 and 24 correspond to measurements on the S-scale of 30 and 60, respectively.  What measurement on the R-scale corresponds to a measurement of 100 on the S-scale?

A.     20

B.     36

C.     48

D.     60

E.      84

答案是C，请指点一下，谢谢大家！

Q10:

A certain quantity is measured on two different scales, the R-scale and the S-scale, that are related linearly.  Measurements on the R-scale of 6 and 24 correspond to measurements on the S-scale of 30 and 60, respectively.  What measurement on the R-scale corresponds to a measurement of 100 on the S-scale?

 A 20

 A 20

 A 20

 B 36

 B 36

 B 36

 C 48

 C 48

 C 48

 D 60

 D 60

 D 60

 E 84

 E 84

 E 84

这题是啥意思啊。。。

考比例尺的关系

可以设联立方程式如下:

30=A+6B

60=A+24B

解联立得A=20, B=5/3

代入 >> 100=20+5/3R

R=48

这题是啥意思啊。。。

考比例尺的关系

可以设联立方程式如下:

30=A+6B

60=A+24B

解联立得A=20, B=5/3

代入 >> 100=20+5/3R

R=48

这题是啥意思啊。。。

考比例尺的关系

可以设联立方程式如下:

30=A+6B

60=A+24B

解联立得A=20, B=5/3

代入 >> 100=20+5/3R

R=48