Cylinder:
Diameter =42 m ⇒ Radius (r)=21 m
Height (h)=21 m
C.S.A. Cylinder =2πrh square cm
=2×227×21×21
=2772m2
Cone:
Radius (r)=21 m, Height (h)=28 m
l=√42+r2
=√282+212
=√1225=35 m
C.S.A. of cone =πrl square cm
=227×21×35=2310m2
Total surface area of circus tent
=2772+2310=5082m2
The cost of 1 square metre = Rs. 12.50
Total cost of canvas =5082×12.50= Rs. 63,525