Multiple choice general knowledge math & puzzles

A rectangle has the dimensions of 14 cm x 10 cm. It's length is reduced by 'x' cm and it's breadth is increased by 'x' cm to make it a square. It's area changes by -

  1. 4

  2. 144

  3. 12

  4. 2

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Original area = 14 * 10 = 140. To make it a square, (14-x) = (10+x), so 2x = 4, x = 2. New dimensions are 12 * 12 = 144. The area changes from 140 to 144, a difference of 4. 144 is the new area, not the change.