Find the missing number

Front

37 + ___ = 80

Back

43

Front

22 + ____ = 60

Back

38

Front

28 + ___ = 80

Back

52

Front

41 + ____ = 90

Back

49

Front

43 + ____ = 80

Back

37

Front

What is the missing number in 15 + ___ = 30?

Back

15

Front

If 50 + ___ = 100, what is the missing number?

Back

50

Front

What number do you add to 10 to get 25?

Back

15

Front

In the equation 60 + ___ = 100, what is the missing number?

Back

40

Front

What is the missing number in 5 + ___ = 20?

Back

15