Question

In an examination, the score in each of the four languages – Bengali, Hindi, Urdu and Telegu- can be integers between 0 and 10. Then the number of ways in which a student can secure a total score of 21 is
(A) 880;
(B) 760;
(C) 450;
(D) 1360.

Comments

is the answer 880??

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Yes @Akriti sood .But how?Can you please explain that?

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Use Generating Function concept and find the coefficient of $x^{21}$ in $(1+x+x^{2}+x^3 + ...+ x^{10})^4$ ,you'll get $880$ .

Reference