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Parimal has done 1/4 th of a job in 10 days, Salim completes the rest of the job in 20 days. In how many days can they together do the job?
- A8 days
- B24 days
- C12 days
- D16 days
Answer not set
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0
CCommunity
I think option 4 is the right answer
0
CCommunity
Let total work to be done $= 80$ units
Work done by Parimal in 10 days $= \frac{1}{4} \times 80 = 20$ units
Parimal's efficiency $= \frac{20}{10} = 2$ units/day
Remaining work $= 80 - 20 = 60$ units
Salim completes $60$ units in $20$ days
=Salim's efficiency $= \frac{60}{20} = 3$ units/day
(Parimal + Salim)'s 1 day's work $= 2 + 3 = 5$ units/day
$\therefore$ Time taken by them together to do the job $= \frac{80}{5} = 16$ days
Work done by Parimal in 10 days $= \frac{1}{4} \times 80 = 20$ units
Parimal's efficiency $= \frac{20}{10} = 2$ units/day
Remaining work $= 80 - 20 = 60$ units
Salim completes $60$ units in $20$ days
=Salim's efficiency $= \frac{60}{20} = 3$ units/day
(Parimal + Salim)'s 1 day's work $= 2 + 3 = 5$ units/day
$\therefore$ Time taken by them together to do the job $= \frac{80}{5} = 16$ days