question_answer

The internal and external radii of a hollow hemispherical bowl are 15 cm and 16 cm respectively, find the cost of painting the  owl at the rate of 35 paise per\[c{{m}^{2}},\]if

(i) the area of the edge of the bowl is ignored.

(ii) the area of the edge of the bowl is taken into account.

A)

(i)	(ii)
Rs. 1058.20	Rs. 1092.30

           

B)

(i)	(ii)
Rs. 1020.50	Rs. 1045

           

C)

(i)	(ii)
Rs. 1092.50	Rs. 1058.20

           

D)

(i)	(ii)
Rs. 1086.20	Rs. 1095.2

Correct Answer: A

Solution :

        Internal radius of the bowl (r) = 15 cm External radius of the bowl (R) = 16 cm (i) If area of edge is ignored, then Surface area of bowl Cost of painting area of the bowl = Rs. 0.35 Cost of painting area of the bowl Rs. 1058.20 (ii) If area of edge is counted, then Surface area of bowl Cost of painting area Rs. 1092.3