Question

If the radius of the cylinder is increased by 10% and its height is increased by 20%, then the percentage increased in the volume ?
(a) 50% (b) 40% (c) 45.2% (d) 46%
If the radius of the cylinder is increased by 10% and its height is increased by 20%, then the percentage increased in the volume ?
(a) 50% (b) 40% (c) 45.2% (d) 46%
@Mathematics

Answer 1

(c)

Answer 2

Can you explain.

Answer 3

when the radius is increased by 10%, the volume will increase by 21%
when height is increased by 10%, calculate the total increase

Answer 4

u got it?

Answer 5

when the radius is increased by 10%,why the volume will increase by 21% ?

Answer 6

well, the base area is proportional to the square of the radius.
so, if radius is r, base will be pi*r^2
when r is increased by 10%, it will be pi*(1.1r)^2=1.21pi r^2
similarly, height will be 1.2 h from h
so, the volume will be 1.21*1.2pi*r^2*h=1.452pi r^2h
previous volume was pi r^2*h
so, the volume will increase by 45.2 % :)

Answer 7

now, is it clear?

Answer 8

How to calculate, how much percentage it increased?

Answer 9

How did you conclude to this part "so, the volume will increase by 45.2 % "

Answer 10

1.453V is 145.2 % of the initial volume V so the increase is 145.2%-100%=45.2 %