Question

If the radius of a circle with a area of 5.3 mm squared is multiplied by 5,

Answer 1

I'm guessing the question is meant to be "If the radius of a circle with a area of 5.3 mm squared is multiplied by 5, what will the new area be?", so i'll answer that.

Area of a circle =πr^2

5.3=πr^2, 5.3=π(5r)^2
132.5=25πr^2