Please help. WILL MEDAL! @mathmale @surjithayer @ganeshie8 @Hero @Kainui @TheSmartOne @Preetha @SolomonZelman @zepdrix @rebeccaxhawaii @Vocaloid @Miracrown @dtan5457
The big man could do 1/3 of a job in 4 hours. The little man could do 1/2 of a job in 2 hours. If the little man needed to complete 30 jobs and worked for 2 hours alone and then was joined by the big man, how long did it take them both to finish the remaining jobs?
Total is 30 jobs, right?
Yes
The rate of the big man is 1/12
Little man does 1/2 job in 2 hours, and he does alone in 2 hours. That means, the leftover is 29.5 jobs, ok?
The rate of the little man is 1/4
Yes.
Their combined rate is 1 job/ 3 hours
So I have to find how long it will take both of them to complete 29.5 jobs with a combined rate of 1/3
Now, for 29.5 jobs. The Little man work 1/2 job in 2 hours. Hence, to finish 1 job, he has to spend 4 hours, ok?
Understood.
so, in 12 hours, how many jobs has he done?
3 jobs
But the 2 of them combined can do 4 jobs
ok now for the Big man, he needs 12 hours to finish 1 jobs. Hence in 12 hours, both combine to get 4 jobs done. right?
yes
So, in 84 hours, they get 28jobs done.
That's correct
12 hours /4 jobs 1 jobs/ 3 hours
1.5 jobs/4.5 hours, right?
1.5 jobs in 4.5 hours
Yep
so, combine all, they need 88 hours 30 minutes, right?
That's right, Thank You!
ok
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