31 out of 50 is
62%Divide 31 over 50:

Multiply 0.62 and 100. This will convert the decimal to a percentage:
11=27
12=27
13=4
14=16
15=24
16=?
sorry I couldn't solve them all, hope that helped :D
Steps to solve:
25 = x + 19
~Subtract 19 to both sides
6 = x
Best of Luck!
The formula for the sum of the a finite geometric series is this:
Sn = a((1-r^n) / (1-r))
The given values are:
n = 30
a = 0.5 mi
r = 1.10 (10% more each day)
S30 = 0.5 ((1-1.10^30) / (1-1.10))
S30 = 82.25 mi
After 30 days, he will have traveled 82.25 miles.