If the number of seven-digit numbers, such that the sum of their digits is even, is m × n × 10 n ; m, n in\ 1,2,3, ldots, 9\ , then m+n is equal to

Mathematics · Permutations and Combinations

JEE Main 2025 — 3 April, Morning Shift — Question 43

If the number of seven-digit numbers, such that the sum of their digits is even, is $m \cdot n \cdot 10^{\mathrm{n}}$ ;

$m, n \in\{1,2,3, \ldots, 9\}$ , then $m+n$ is equal to

Numerical answer — enter this value.

Total 7 digit nos. $=9000000$

7 digit nos. having sum of digits

Even $=4500000$

$=9.5 \cdot 10^{5}$

$\mathrm{m}=9, \mathrm{n}=5$

$\mathrm{m}+\mathrm{n}=14$

Answer key and solution verified before publishing.

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