If number of five digit numbers with distinct digits and 2 at 10^{text {th }} place is 336 mathrm{k}

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6.Permutation and Combination

hard

If the number of five digit numbers with distinct digits and $2$ at the $10^{\text {th }}$ place is $336 \mathrm{k}$, then $\mathrm{k}$ is equal to

A

$8$

B

$6$

C

$4$

D

$2$

(JEE MAIN-2020)

Solution

$\_ \;\_\;\_\;\underline2\;\_$

No. of five digits numbers $=$ No. of ways of filling remaining 4 places $=8 \times 8 \times 7 \times 6$

$\mathrm{k}=\frac{8 \times 8 \times 7 \times 6}{336}=8$

Standard 11

Mathematics

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