### Home > PC > Chapter 4 > Lesson 4.2.1 > Problem 4-76

4-76.

A circle of radius 10 cm cut out of cardboard weighs 120 g. Homework Help ✎

How much would a 60° sector weigh?

How much would a circle of radius 15 cm cut out of the same cardboard weigh?

What part of the entire cardboard would 60° represent?

What is the area of a circle?

Set up information involving area and weight.

Set up a proportion and solve for the new weight.

A_{circle} = π*r*^{2}

A_{original} = 100π

Weight_{original} = 120

A_{new} = 15²π = 225π

Weight_{new} = ???