Answer:
25
Explanation:
Positive integers less than 250 are 1, 2, 3, ..., 248, 249.
Positive multiples of 5 that are not multiples of 10 are integers than end in 5.
5, 15, 25, 35, ...
In each group of 10 consecutive integers, 1 through 10, 11 through 20, etc. there is one integers ending in 5. From 1 to 250, there are 25 groups of 10 consecutive integers, so there are 25 integers that end in 5.
Answer: 25