Answer:
number is 4
Step-by-step explanation:
let 'n' = the number
2(n + 18) = 9n + 8
2n + 36 = 9n + 8
36 = 7n + 8
28 = 7n
n = 4
problem can't be solved
2.5*15 is 37.5 miles so he has run more than 30 miles in 15 days.
picture is attached
there are many options but this is one