Problema Solution
You and your brother start a house cleaning service over the summer. Your brother takes twice as long as you on a certain room but together it takes you 60 minutes to clean the room. How long would it take you to clean the certain room by your self?
Answer provided by our tutors
suppose you take x and your brother takes 2x
1/x + 1/2x = 1/60
3/2x = 1/60
x = 3*60/2
x = 90
you take 90 minuts.