Asmall grill can hold two hamburgers at a time. if it takes 5 minutes to cook one side of a hamburger, what is the shortest time needed to cook both sides of five hamburgers?

If you were to grill two hamburgers at the same it would take 5 minutes to grill one side of 2 hamburgers and ten minutes to grill 2 ham burgers on both sides. So 10 minutes would make two hamburgers while 20 minutes will cook 4 hamburgers than add and extra 10 minutes to cook the last hamburger on both sides.
10 minutes = 2 both side cooked hamburgers
+ 
10 minutes = 2 both side cooked hamburgers
+ 
an extra 10 minutes = another both side cooked hamburgers since we only need five
=
30 minutes in minimal time to cook five hamburgers

5(2a-5+b). xbox xboxxbx xb