Question

the radius and height of a cylinder are in the ratio 5:7 and its volume is 550 cm3. find its radius and ratio of curved surface to its surface area

Answer 1

r/h=5/7
h/r=7/5
h = 7r/5
r=5h/7

V=pi x r x r x h
550 = 22/7 x r x r x 7r/5
550 = 22 x r x r x r x 5
550 = 110 x r x r x r
5 = r x r x r
r ^ 3 = 5
r = 5 ^ ( 1 / 3 )
r = 1.71 cm
cs A: TSA = 2pirh:2pir(r+h)