Problema Solution
Gary and his assistant can rake the sand on a beach volleyball court together in 20 min. if his assistant could do it alone in 70 minutes, how many mins would it take for Gary to rake the court by himself?
Answer provided by our tutors
gary +asst one minute work = 1/20
assistant = 1/70
hence gary 1 minute work = 1/20-1/70 = 50/1400 = 1/28
hence gary can do in 28 minutes