SOLUTION: Two workers can do a job in 33/7 hours.THe first one can do the same job in 6 hours. How much time will it take for the second one to complete the job if he works alone ? PL

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Question 129665: Two workers can do a job in 33/7 hours.THe first one can do the same job in 6 hours. How much time will it take for the second one to complete the job if he works alone ?

PLZZZ !! DO HELP ME ! I hv an exam tomorrow abd i dont understand this ! If someone helps me than god bless him !! PLZ
Found 2 solutions by checkley71, ptaylor:
Answer by checkley71(8403) (Show Source):
You can put this solution on YOUR website!
6X/(6+X)=33/7 NOW CROSS MULTIPLY.
6X*7=33(6+X)
42X=198+33X
42X-33X=198
9X=198
X=22 HOURS FOR THE SECOND WORKER IF HE WORKS ALONE.
PROOF:
6*22/(6+22)=33/7
132/28=33/7
28*33=132*7
924=924

Answer by ptaylor(2198) (Show Source):
You can put this solution on YOUR website!
Let x= amount of time required for the second worker to complete the job if he works alone
The two workers work at the rate of 1/(33/7) of the job per hour. This reduces to 7/33 of the job per hr (As you can see 7/33 of the job per hour times 33/7 hours = one job completed)
The first worker works at the rate of 1/6 of the job per hour.(Again, as you can see 1/6 of the job per hour times 6 hours = 1 job completed). (R U getting the idea??)

Now he second worker does 7/33-1/6 of the job per hour. This reduces to:
14/66-11/66 or 3/66 of the job per hour and this reduces to 1/22 of the job per hour.
Now our equation to solve is:
(1/22)*x=1 (job completed) Multiply both sides by 22/1
x=22 hrs
CK
First worker works at the rate of 1/6 job per hr
Second worker works at the rate of 1/22 job per hr.
1/6+1/22=11/66+3/66=14/66 of the job per hr and this reduces to
7/33 of the job per hr
(7/33)*33/7=1
1=1

Hope this helps---ptaylor