Sally ran 2 1/5 miles on 3 different days in the week. She ran 1 1.5 miles on 1 other day. How many miles did she run in total?

Calculate 3 (2 1/5 miles) + 1 (1.5 miles) (I don't think you really meant "11.5 miles).

6 3/5 + 1.5 = 6.6 + 1.5 = 8.1 miles.

Looking again at your post, I'm wondering whether your "1 1.5 miles" was supposed to mean "1 1/5 miles."

If so, the correct answer is different from the first one:

3 (2 1/5 miles) + 1 (1 1/5 miles) = 6 3/5 miles + 1 1/5 miles = 7 4/5 miles.