Question 380944
together they can finish in 8 hours.
together they do 1/8 of the job in 1hour.
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cousin takes 10 hours.
so cousin does1/10 of the job in 1 hour.
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so you can do 1/8 -1/10 of the job in 1 hour.
LCD = 40
(5-4)/40 of the job you can do in 1 hour
=1/40 of the job.
 so you will take 40 hours to do the job 
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m.ananth@hotmail.ca