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Ansh and Tanvi can do a piece of work in 24 days and 40 days, respectively. They started the work, and after 8 days, Shubham, who can complete the same work in 20 days alone, joined them. In how many days can the whole work be completed?
16 days
15 days
12 days
20 days
16 days
Use LCM of 24, 40, 20 as 120 units. Ansh's efficiency is 5, Tanvi's is 3, Shubham's is 6. After 8 days of (5+3)=8 units/day, 64 units are done. Remaining 56 units are done by (5+3+6)=14 units/day in 4 more days. Total = 8+4 = 12 days.
Ansh takes 24 days, Tanvi takes 40 days. They work together for 8 days, then Shubham (who takes 20 days alone) joins.
Total┬аWork=LCM(24,40,20)=120unitsEfficiency=TimeWorkтАЛ
Use LCM of 24, 40, 20 as 120 units. Ansh's efficiency is 5, Tanvi's is 3, Shubham's is 6. After 8 days of (5+3)=8 units/day, 64 units are done. Remaining 56 units are done by (5+3+6)=14 units/day in 4 more days. Total = 8+4 = 12 days.
Many students add Shubham's work to the total but forget he only joins after the first 8 days, or they calculate only the days he worked.
Calculate LCM and Efficiencies
Assume total work as LCM(24, 40, 20) = 120. Efficiencies are Ansh=5, Tanvi=3, Shubham=6.
120┬аunits,EAтАЛ=5,ETтАЛ=3,ESтАЛ=6
Calculate work done in first 8 days
Ansh and Tanvi work together for 8 days at a rate of 5 + 3 = 8 units/day.
W1тАЛ=8├Ч8=64┬аunits
Calculate remaining work and time with Shubham
Remaining work is 120 - 64 = 56. With Shubham, total efficiency is 5 + 3 + 6 = 14 units/day.
T2тАЛ=1456тАЛ=4┬аdays
Total time calculation
Adding the initial 8 days and the final 4 days.
8+4=12┬аdays
C is correct because the total work takes 8 + 4 = 12 days to complete.
This is a standard work-time variation; always define total work as the LCM of time taken by individual workers to simplify fractions.