Which two numbers have a mode of 10 and a range of 8?

The modes is the number which occurs most often. The range is the biggest number - the smallest number. The only way to have a mode of 10 and a range of 8, is to have the two numbers be 10 and 2. The numbers are different so each is a mode and the range is 10-2-8.

Note, 2 is also a mode in the set {2,10}.