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प्रश्न
Find the value of 15C4
उत्तर
15C4 = `(15!)/(4!(15 - 4)!)`
= `(15!)/(4!11!)`
= `(15 xx 14 xx 13 xx 12 xx 11!)/(4 xx 3 xx 2 xx 1 xx 11!)`
= `(15 xx 14 xx 13 xx 12)/(4 xx 3 xx 2 xx 1)`
= 1365
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