Subtract till 100

Calculate:

The number of examples:
Numerical difficulty:
Range of values:
Multiplicity:

62	-	11	=
97	-	5	=
87	-	4	=
47	-	15	=
88	-	15	=
53	-	4	=
43	-	25	=
96	-	33	=
71	-	5	=
47	-	11	=