Subject
Bank Exam
Topic
Prime Bank Ltd. MTO 2013
The radius of a circle is increased by 10%, then the area is increased by what percent?
The radius of a circle is increased by 10%, then the area is increased by what percent?
ক)
10%খ)
20%গ)
21%ঘ)
100%Explanation
Area of circle A = π*r2 Increase r by 10% new area is: π*(1.1r)2 = 1.21*π*r2 thus area is increased by (1 - 1.21) = 0.21 = (0.21*100)% = 21%Related questions
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