The answer to the solution is:
X= 7
9x+13=2x+48
-2x -2x
7x+13=48
-13 -13
7x=35
/7 /7
x=5
y=9(5)+13
y=45+13
y=58
To solve you first need to pick out the most important information,
~Spent 20 minutes
~Each prob takes 2 minutes
Lets have y be the total time spent, and x the number of probs
(y/2) = x
Hope this helped!! ^-^
