Question
In how ways can the selection be made so that a
particular member is always included? There are 5 members in a delegation which is to be sent abroad. The total no. of members is 11.ÂSolution
As the person is always included, therefore, ∴ C_1 × 10C_4  =  1 × (10 × 9 × 8 × 7)/(4 × 3 × 2)  = 210
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