Adding till 400

Calculate:

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

150	+	80	=
18	+	15	=
146	+	142	=
124	+	170	=
17	+	8	=
135	+	96	=
14	+	15	=
42	+	48	=
104	+	142	=
153	+	145	=