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

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13.Statistics

easy

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

A

$15$

B

$12$

C

$24$

D

None of these

Solution

(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$

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

Standard 11

Mathematics

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