Directions: Q. 21 to 25 |
Committee of a club select a round glass trophy for awarding best director in film festival. Design of each trophy is made as shown in the figure, where its base PQRS is golden plated from the front side and painted at the rate of Rs 5 per\[c{{m}^{2}}\]. |
A) \[254\text{ }c{{m}^{2}}\]
B) \[348\text{ }c{{m}^{2}}\]
C) \[344.5c{{m}^{2}}\]
D) \[346.5c{{m}^{2}}\]
Correct Answer: D
Solution :
The area OSRO is one-fourth of the total area. \[\therefore \]Area of the sector \[=\frac{1}{4}\pi {{r}^{2}}\] \[=\frac{1}{4}\times \frac{22}{7}\times 21\times 21\] \[\left[ \because \,\,r=21\,cm \right]\] \[=\frac{9702}{28}\] \[=346.5\,\,\,c{{m}^{2}}\]You need to login to perform this action.
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