First, you need to notice that both numbers can be turned into fractions.
2 miles 40 minutes: 1/20
2 miles 25 minutes: 2/25
Also notice how most percentages are out of 100? So we have half a fraction we need to turn both of the numbers into.
1/20 = ?/100
2/25 = ?/100
The answer to 1/20 is 5/100, and for 2/25, it's 8/100. Now, we need to add both of the percentages.
5 + 8 = 13
Your answer is 13%. I hope this helps! :)