What is the area of the border?

Question

A rectangular living room measures 12 feet by 10 feet.
A carpet placed on the floor leaves a border 2 feet wide all around it.
What is the area of the border?

Answer 1

If you draw the 12ft x 10ft rectangle

draw another rectangle inside that ...

 

Given the 2ft wide open space around the edge of

the carpet the inside rectangle has dimensions of

8ft x 6ft

 

If we subtract the area of the carpet from the

area of the whole room the difference is the

area of the open space between carpet and walls

 

Room = 12(10) = 120 ft²

Carpet = 8(6) = 48 ft²

 

Open space = 120 - 48 = 72 ft²