| Peter can mow the lawn in 40 minutes and John can mow the lawn in 60 minutes. How long will it take for them to mow the lawn together? |
Time for PETER alone is 40 Minutes.
Time for JOHN alone is 60 Minutes.
Let T = Time together in Minutes.
1 1 1
-- + -- = -
40 60 t
LCM of 40 and 60 = 600.
15 + 10 1
------- = -
600 t
25 1
----- = -
600 t
600
t = ----- Minutes
25
GCF of 25 and 600 = 25.
t = 24 Minutes
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