A tent is of the shape of a right circular cylinder upto a height of 3 metres and then becomes a right circular cone with maximum height of 13.5 metres above the ground. If the radius of the base is 14 metres, the cost of painting the inner side of the tent at the rate of Rs. 2 per square metre is

$=sqrt{(10.5)^{2}+14^{2}}=sqrt{110.25+196}$

$=sqrt{306.25}=17.5$ metre

Curved surface area of the cone=Srl

$=frac{22}{7} imes 14 imes 17.5=770$ sq.metre

Curved surface area of cylinder = 2Sr h

$=2 imes frac{22}{7} imes 14 imes 3=264$ sq.metre

∴ Total area = 264 + 770 = 1034 sq.metre

∴ Total cost = 2 × 1034 = Rs. 2068