Sahil can complete a job in 20 days when working alone. Manoj is twice as fast as Sahil and three times as fast as Ashish in the same job. The collaborative work arrangement involves Sahil and Manoj working on the first day, Sahil and Ashish on the second day, and Manoj and Ashish on the third day. This three-day cycle continues till the work is complete.
What fraction of the total work will then be done by Ashish till the job is completed?
Sahil can complete a job in 20 days when working alone. Manoj is twice as fast as Sahil and three times as fast as Ashish in the same job. The collaborative work arrangement involves Sahil and Manoj working on the first day, Sahil and Ashish on the second day, and Manoj and Ashish on the third day. This three-day cycle continues till the work is complete.
What fraction of the total work will then be done by Ashish till the job is completed?
Solution
Take total work units (LCM of , and ).
Sahil does the job in days, so Sahil does units/day.
Manoj is twice as fast as Sahil, so Manoj does units/day.
Manoj is three times as fast as Ashish, so Ashish does units/day.
Day 1 (Sahil + Manoj) units
Day 2 (Sahil + Ashish) units
Day 3 (Manoj + Ashish) units
One -day cycle units, of which Ashish does units.
Two full cycles ( days) units. Remaining units
Day 7 (Sahil + Manoj) units. Remaining units
Day 8 (Sahil + Ashish) units. Remaining units
Day 9 (Manoj + Ashish) do units in a full day, so units need day.
Ashish's work on day 9 unit
Ashish's total work (two cycles) (day 8) (day 9)
units
Fraction
Therefore, Ashish does of the total work.