Question

The two solids below are similar, and the ratio between the lengths of their edges is 4:5. what is the ratio of their surface areas?

a.16:25
b.16:20
c.5:4
d.64:125

Answer 1

ratio of the areas is 4^2: 5^2  = 16:25  (answer).

Answer 2

Keep in Mind, when two shapes or polygons are similar , the ratio of their areas is equal to square of their corresponding sides or edges.

As given, Ratio of the edges of two solids =
`(4)/(5)`

Ratio of their Surface areas

= ( Ratio of the edges of two solids)²=
`((4)/(5))^2`

=
`(16)/(25)`

Option A: 16: 25 is true.