Question

he radius of a right circular cylinder is increasing at a rate of 7.5 inches per minute and the height is decreasing at a rate of 13.5 inches per minute. What is the rate of change of the surface area when the radius is 15.5 inches and the height is 33 inches

Answer 1

Answer:Rate of change of the surface area =876.85 square inches

Explanation:

Surface area of a cylinder=2*pie*radius*height

Former radius and height are 8.0inches(15.5-7.5) and 46.5inches(33+13.5) respectively

New radius and height are 15.5inches and 33 inches respectively.(pie 22/7)

2*22*8*46.5=16368/7=2338.29

Also 2*22*15.5*33=22506/7=3215.14

Rate of change is 3215.14-2338.29=876.85inches