cylindrical pipe has an outer diameter of 14 cm and inner diameter of 11.2cm. Its length is 20 cm. It has to be painted on its outer and inner surface,as well as on its rims at the top and bottom. If the rate of painting is rupees is 0.07 per cm square,find the total cost of painting the pipe.
Answers
Answer:
Step-by-step explanation:
Total area to be painted = outer surface + inner surface + rims of top and bottom;
Lateral surface are of cylinder = 2 pi * h* r
Outer surface = 2*3.14*20*14 = 1758.4 sq.cm.
Inner surface = 2*3.14*20*11.2 = 1406.72 sq.cm.
Surface of top rim = pi (14^2-11.2^2) = 221.58 sq.cm.
Surface of top rim = same as top rim = 221.58 sq. cm
Total area = 1758.4+1406.72+2*221.58 = 3608.28 sq. cm
per sq. painting cost = 0.07 rupees ;
total cost to painting = 3608.28*0.07 = 252.57 rupees
Answer:
Total area to be painted = outer surface + inner surface + rims of top and bottom;
Lateral surface are of cylinder = 2 pi *h* r
Outer surface = 2*3.14*20*14 = 1758.4
sq.cm.
Inner surface = 2*3.14*20*11.2 = 1406.72 sq.cm.
Surface of top rim = pi (14^2-11.2^2) = 221.58 sq.cm.
Surface of top rim = same as top rim = 221.58 sq. cm
Total area = 1758.4+1406.72+2*221.58 = 3608.28 sq. cm
per sq. painting cost = 0.07 rupees;
total cost to painting = 3608.28*0.07 = 252.57 rupees