Maths - Finding the missing number

3  +  2  =  4  +  ____

We start doing the operation on one side.

3  +  2  =  5

What do we have to add to the other side so that the balance is equal?

4  +       =  5

4  +  1  =  5
 

The answer is 1

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Find the missing numbers:

2  +  4  =  5  +  _____

3  +  5  =  4  +  _____

8  +  3  =  5  +  _____

6  +  3  =  3  +  _____

2  +  _____ =  1  +  3

4  +  _____  =  6  +  1