Answer
The ratio of the perimeters of two smaller figures is equal to $2:5$, and the ratio of the areas $4:25$.
Work Step by Step
We are given that scale factor $=2:5$
We can see that the ratio of the perimeters of two smaller figures is $\dfrac{a}{b}$, and the ratio of their areas is the square of the ratio of their perimeters:
$\dfrac{a^2}{b^2}$.
Now, the ratio of the perimeters of two smaller figures is equal to $2:5$
So, the ratio of the areas is equal to the square of the scale factor, which is $2^2:5^2=4:25$.
