Question

1. The curved surface area of a cylinder of height 21cm is
660cm", find its radius. please help me .....
I will give brainliest. ​

Answer 1

Answer:

21 times 660 and then you will get the answer

Answer 2

Mark Brainliest please

Answer: 5 cm

Step-by-step explanation:

Curved Surface area of a cylinder formula :-

2.pie*r*h (where r is the radius)
Height = 21 cm

Curved Surface area of the cylinder = 660 cm2

So, 2* pie* r* h = 660 (Here I will assume pie to be 22/7)

And 2* 22/7 * 21* r = 660

And 132 * r = 660
Therefore, r = 660/132 = 5cnn

Therefore radius of the cylinder = 5 cm