Adding till 400

Calculate:

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

142	+	157	=
104	+	114	=
59	+	79	=
109	+	80	=
174	+	177	=
27	+	28	=
85	+	116	=
153	+	116	=
98	+	231	=
155	+	142	=