A) 100
B) 99
C) 102
D) 101
Correct Answer: D
Solution :
[d] \[{{\left( \frac{8}{5} \right)}^{2}}+{{\left( \frac{12}{5} \right)}^{2}}+{{\left( \frac{16}{5} \right)}^{2}}+{{\left( \frac{20}{5} \right)}^{2}}....+{{\left( \frac{44}{5} \right)}^{2}}\] \[S=\frac{16}{25}\left( {{2}^{2}}+{{3}^{2}}+{{4}^{2}}+....+{{11}^{2}} \right)\] \[=\frac{16}{25}\left( \frac{11(11+1)(22+1)}{6}-1 \right)\] \[=\frac{16}{25}\times 505=\frac{16}{5}\times 101\] \[\Rightarrow \,\,\frac{16}{5}m=\frac{16}{5}\times 101\Rightarrow m=101.\]You need to login to perform this action.
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