If the radius of a circle is doubled, by what factor does its area increase?
A2
B3
C4CORRECT
D6
JAMB UTMEMathematics
AI
Toaster Teacher
Why the answer is C, and why the others tempt you.
Area = πr². If r becomes 2r, area becomes π(2r)² = 4πr². So 4× original.
Want this in Pidgin, Yoruba, Igbo or Hausa? Sign up free →
Practice more Mathematics questions
JAMB UTME Mathematics has thousands more questions like this — with Worked answers on every one.