A rectangle stone has a width of 4/5 inch and an area of 7/10 square inch. Is a silver wire with a length of 3 1/2 inches long enough to outline the stone?

Question

A rectangular stone has a width of 4/5 inch and an area of 7/10 square inch. Is a silver wire with a length of 3 1/2 inches long enough to outline the stone?

Answer 1

We find the length by dividing the area by the width=7/10÷4/5=7/10×5/4=7/8 in.

The perimeter (outline) is 2(4/5+7/8)=67/20=3+7/20. We subtract this from 3+½, and we have 1/2-7/20=3/20.

This is a positive number. This means that the wire is longer than the outline of the stone, so, yes, it will outline it.