Multiple choice general knowledge math & puzzles

What is the % change in the area of a rectangle when its length increases by 10% and its width decreases by 10%?

  1. 1% decrease

  2. 1% increase

  3. 20% decrease

  4. 20% increase

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

The original area is L × W. After changes, new area = 1.1L × 0.9W = 0.99LW. This is a 1% decrease overall. The 10% increase and 10% decrease don't cancel out exactly - they multiply to 0.99, giving a net loss.