2015 · Q85
A rectangular paper of 44 cm long and 6 cm wide is rolled to form a cylinder of height equal to width of the paper. The radius of the base of the cylinder so roiled is
Elementary MathematicsMensuration
- A3.5 cm
- B5 cm
- C7 cm
- D14 cm
Explanation
This is a circumference-to-radius conversion. Rolling the 44 cm side into the circumference: 2πr = 44, so r = 44/(2π) = 7 cm with π = 22/7. Option (a) 3.5 cm is the trap from halving again (confusing circumference with diameter). Hence option (c).