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If Sam can do a job in 4 days that Lisa can do in 6 days and Tom can d 29 Jul 2019, 06:40
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B
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82% (01:13) correct 18% (01:16) wrong based on 174 sessions

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If Sam can do a job in 4 days that Lisa can do in 6 days and Tom can do in 2 days, how long would the job take if Sam, Lisa, and Tom worked together to complete it?

A. 0.8 days
B. 1.09 days
C. 1.23 days
D. 1.65 days
E. 1.97 days
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B
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If Sam can do a job in 4 days that Lisa can do in 6 days and Tom can d 29 Jul 2019, 07:00
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Rate of Sam(Rs)=1/4; Rate of Lisa(Rl)=1/6; and Rate of Tom(Rt)=1/2
Rate of three working together, Re=Rs+Rl+Rt
Re=1/4+1/6+1/2=11/12
Time taken by the three working together =1/Re =12/11=1+1/11=1+0.0909=1.09
Hence B is the answer.

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If Sam can do a job in 4 days that Lisa can do in 6 days and Tom can d 29 Jul 2019, 07:49
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1/4 + 1/6 + 1/2= 1/x
(3+2+6)/12=1/x
11/12=1/x
x=12/11=1.09

The answer choice is B

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If Sam can do a job in 4 days that Lisa can do in 6 days and Tom can d 29 Jul 2019, 07:58
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Bunuel
If Sam can do a job in 4 days that Lisa can do in 6 days and Tom can do in 2 days, how long would the job take if Sam, Lisa, and Tom worked together to complete it?

A. 0.8 days
B. 1.09 days
C. 1.23 days
D. 1.65 days
E. 1.97 days
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Given: Sam can do a job in 4 days that Lisa can do in 6 days and Tom can do in 2 days.

Asked: How long would the job take if Sam, Lisa, and Tom worked together to complete it?

Sam can do 1/4 work in a day
Lisa can do 1/6 work in a day
Tom can do 1/2 work in a day

Sam, Lisa & Tom can do 1/4+1/6+1/2 =11/12 work in a day
How long would the job take if Sam, Lisa, and Tom worked together to complete it = 12/11 = 1.09 days

IMO B
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If Sam can do a job in 4 days that Lisa can do in 6 days and Tom can d 29 Jul 2019, 08:08
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let the work be 12 unit,
Sam does it in 4 days , so 3 unit per day
similarly, Lisa 2 unit, and Tom 6 unit
if all three work together, its 11 unit in a day
and 12/11 days to complete the work , so 1.09

B is the answer
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If Sam can do a job in 4 days that Lisa can do in 6 days and Tom can d 12 May 2023, 08:34
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Bunuel
If Sam can do a job in 4 days that Lisa can do in 6 days and Tom can do in 2 days, how long would the job take if Sam, Lisa, and Tom worked together to complete it?

A. 0.8 days
B. 1.09 days
C. 1.23 days
D. 1.65 days
E. 1.97 days
Show more
Let, the total work be 12 units...

Efficiency of Sam = 3 units/Day ; Efficiency of Lisa = 2 units/Day & Efficiency of Tom = 6 units/Day

Thus, combined efficiency of Sam, Lisa, and Tom is 11 units/day

Time required to complete 12 units will be 12/11 = 1.xx (Little more than 1), thus Answer must be (B)
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If Sam can do a job in 4 days that Lisa can do in 6 days and Tom can d 24 Jun 2024, 06:49
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