Subtract till 400

Calculate:

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

160	-	107	=
247	-	49	=
357	-	96	=
188	-	55	=
391	-	62	=
356	-	172	=
173	-	172	=
133	-	73	=
219	-	91	=
195	-	122	=