Adding till 400

Calculate:

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

208	+	137	=
220	+	141	=
136	+	77	=
80	+	107	=
229	+	163	=
136	+	95	=
153	+	159	=
14	+	13	=
152	+	176	=
51	+	76	=