## Question

10 different toys are to be distributed among 10 children. Total number of ways of distributing these toys so that exactly 2 children do not get any toy, is equal to:

### Solution

It is possible in two mutually exclusive cases

**Case – 1: **2 children get none, one child gets three and all

remaining 7 children get one each.

**Case – 2 :** 2 children get none, 2 children get 2 each and all

remaining 6 children get one each.

Using formula given in section (6.3) , we get:

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