Multiple choice

If the circumference of a circle is increased by 50%, then the area will be increased by

  1. 50%

  2. 100%

  3. 125%

  4. 225%
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

If circumference increases by 50%, the radius increases by 50% (r' = 1.5r). Area is proportional to r^2, so new area = (1.5)^2 * original area = 2.25 * original area. This is a 125% increase.

Keep practicing — related questions