Multiple choice

A square carpet when placed in a room leaves a strip $1 m$ wide uncarpeted along one pair of opposite walls and a strip $2 m$ wide along the other two walls. If the area uncarpeted is $62 sq m$, what is the length of the carpet?

  1. $10 m$
  2. $9 m$
  3. $8 m$
  4. $7 m$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Let carpet side be x. Room dimensions are (x+2) and (x+4). Area of room = (x+2)(x+4) = x^2 + 6x + 8. Area of carpet = x^2. Uncarpeted area = (x^2 + 6x + 8) - x^2 = 6x + 8. 6x + 8 = 62, 6x = 54, x = 9.