Subtract till 100

Calculate:

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

98	-	32	=
67	-	22	=
74	-	27	=
98	-	33	=
100	-	38	=
85	-	26	=
19	-	18	=
77	-	14	=
50	-	3	=
72	-	5	=