Question
If $M.D.$ is $12$, the value of $S.D.$ will be

Answer

a
(a) We know that ${\rm{Q}}{\rm{.D}}{\rm{.}} = \frac{5}{6} \times {\rm{M}}{\rm{.D}}{\rm{.}}$$ = \frac{5}{6} \times 12 = 10$

 ${\rm{S}}{\rm{.D}}{\rm{.}} = \frac{3}{2} \times {\rm{Q}}{\rm{.D}}{\rm{.}}$

$ = \frac{3}{2} \times 10$

==> ${\rm{S}}{\rm{.D}}{\rm{.}} = 15$.

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