Question

A rectangular paper is 10 cm wide and 12 pi cm long, it is made of a vertical cylinder of 10 cm high by turning the round and folding the two edges. Find the radius of the cylinder.

Answer 1

first find the area of the rectangle then that will be the curved surface area of the cylinder from there you can find the radius of the cylinder applying the formula

Answer 2

hey!!!

given :-

width of the rectangular paper = 10cm
Length of the rectangular paper = 12πcm = 12×22/7cm
= 264/7cm

it's made from a vertical cylinder of height 10cm.

therefore the width of the rectangular paper is the height of the cylinder. so the length of the rectangular paper is the circumference of the cylinder.

circumference of the cylinder = 264/7cm
>> 2πr = 264/7cm
>> 2 × 22/7 × r = 264/7cm
>> 44/7 × r = 264/7cm
>> r = 264/7×7/44
>> r = 264/44
>> r = 6cm

hence, the radius of the base of the cylinder is 6cm.

cheers!!!