Answer: 5 11/24 ft
First you want to start by making the fractions by have the same denominator. You can just multiply 8 and 6 for this. You should have 14 18/48 and 8 40/48. Subtract them and you get 5 22/48. Simplify it and you get your answer.
Please find the attached photograph for your answer
I am bad at this types of questions but will give you what i would write of the question if i had it
If his run is 16/8 miles per day, 8/10 of the run is 16/8×8/10= 2×8/10
= 16/10
= 1.6
but... i am not sure if the question requires yoi to add the miles from the pervious day as the break was only stated in the second day. If i were you, i will leave the answer as 1.6 miles.