Adding till 400

Calculate:

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

10	+	9	=
175	+	198	=
56	+	34	=
103	+	122	=
61	+	47	=
83	+	84	=
2	+	3	=
197	+	194	=
145	+	179	=
55	+	38	=