Subtract till 400

Calculate:

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

166	-	120	=
274	-	168	=
227	-	141	=
155	-	8	=
200	-	134	=
303	-	195	=
227	-	2	=
383	-	20	=
193	-	111	=
178	-	53	=