Nine less one-fourth of a number is 31. find the number

You love to play soccer! you make a shot at the net 8 times during a game! of those 8 attempts, you score twice. what percent of the time did you score?

On monday, the water was shut off 3 times for 1/4 hours, 2/3 hours, and 1-3/4 hours, respectively. what was the tireless number of hours the water was off?

Ireally don't understand this, i'm really an idiot but i want to know how to figure this out. !