Adding till 100

Calculate:

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

47	+	48	=
25	+	37	=
7	+	8	=
8	+	9	=
17	+	18	=
28	+	42	=
41	+	36	=
49	+	42	=
20	+	32	=
52	+	43	=