Given: We have toys with bearing 4, 4 and 5

To Find: Number of 3-digit numbers he can make

The formula used: The number of permutations of n objects, where p₁ objects are of one kind, p₂ are of the second kind, ..., p_k is of a k^th kind and the rest, if any, are of a different kind is

The child has to form a 3-digit number.

Here the child has two 4’s.

We have to use the above formula

Where,

n=3

p₁=2

The numbers are 544, 454 and 445.

He can make 3 3-digit numbers.