A) 25 cm
B) 22 cm
C) 23 cm
D) 24 cm
Correct Answer: D
Solution :
\[r=\frac{14}{2}=7cm.\] Let h be the height of the cone Then, curved surface \[=\pi \,rl\] \[=pr\sqrt{{{r}^{2}}+{{h}^{2}}}\] \[=\pi \times 7\times \sqrt{{{7}^{2}}+{{h}^{2}}}\] By hypothesis, \[7\pi \sqrt{49+{{h}^{2}}}\] \[=550\] or \[\sqrt{49+{{h}^{2}}}=\frac{550}{7\pi }=\frac{550}{7\times \frac{22}{7}}=25\] or \[49\times {{h}^{2}}={{25}^{2}}=625\] or \[{{h}^{2}}=576\] or \[h=24cm\]You need to login to perform this action.
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