# A and B are two sets such that n(A)=4and n(B)=5.If number of possible mappings defined from set A to B is 'x' and out of these 'y' mappings are one-one , then x+y will be=?

##### 1 Answer

Apr 27, 2018

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#### Explanation:

The number of aplications (mappings) between two sets with cardinals n and m respectively is

In our case, the number of mappings is

The number of inyective mappings (one to one) is