Dividing till 20

Calculate:

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

50	/	10	=
35	/	7	=
80	/	16	=
65	/	13	=
90	/	9	=
56	/	28	=
48	/	8	=
64	/	8	=
45	/	15	=
57	/	19	=