Problema Solution
It takes a groundskeeper 40 minutes to prepare a softball field for a game. It takes his assistant 50 minutes to prepare the same field. How long will it take if they work together to prepare the field?
Answer provided by our tutors
the rate of the groundskeeper is 1 field in 40 min that is 1/40 fields per minute
the rate of his assistant is 1 field in 50 min that is 1/50 fields per minute
the together rate is sum of the their individual rates
1/40 + 1/50 = 9/200
the together rate is 9/200 fields per minute
(9/200) : 1 = 1 : t, where t is the time we are looking for
by solving we find
t = 200/9 = 22.2 min
if they work together they can prepare the field in 22.2 minutes.