Adding till 400

Calculate:

Number of examples:
Numerical difficulty:
Range of values:
Multiplicity:

143	+	127	=
72	+	88	=
184	+	79	=
16	+	21	=
177	+	166	=
11	+	21	=
147	+	100	=
94	+	60	=
83	+	93	=
117	+	138	=