The approximate radius of the cylinder is 4.5m
Surface area of cylinder
The formula for calculating the surface area of cylinder is expressed as:
SA = 2πr(r+h)
where
r is the radius
h is the height
Given the following parameters
SA = 221.1 square meters
height = 7.8m
Substitute
221.1= 2(3.14)r(r+7.8)
221.1 = 6.28r^2 + 15.6r
Factorize to have
6.28r^2 + 15.6r - 221.6 = 0
On factoring, the value of the radius is 4.5 meters
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