Question

What is the ratio for the surface areas of the rectangular prisms shown below,

given that they are similar and that the ratio of their edge lengths is 7:3?
7
21
3
9
6
14
O A. 343:27
B. 9:49
C. 49:9
D. 27:343

Answer 1

Calculating surface area
Big Prism-
7*14*2=196
7*21*2=294
14*21*2=588
196+294+588=1078

Small prism
3*6*2=36
3*9*2=54
6*9*2=108
36+54+108=198

1078:198
Simplify(divide by common factors)
(Divide2)
539:99
(Divide 11)
49:9

C is your answer