Question 331743
Lyman can mow the family yard in 75 mins,
Jean can mow it in 60 mins.
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lyman can do 1/75 of job in 1 minute
jean can do 1/60 of job in 1 minute
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together 
1/75+1/60 = 4+5 /300 
9/300 of the job in 1 minute.
so together they will do in 300/9 minutes
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33.33 minutes
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