If the base radius of a cylinder is increased by 10% and the height remains unchanged, then find the percentage increase in the volume of the cylinder.
Answer & explanation
Correct answer: option 2
Volume of cylinder = πr²h
10% = \(\frac{1}{10}\)
Old New
Radius 10 : 11
Radius 10 : 11
Height 1 : 1
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Volume = 100 : 121
Percentage increase in volume of cylinder = \(\frac{121 - 100}{100}\) × 100%
= \(\frac{21}{100}\) × 100%
= 21%