A and B can do a piece of work in 10 days B and C in 15 days and C and a in 20 days they all worked at first 6 days and then a loose and B and C go on together for 4 days more if 3 then lives how long will it take to complete the work
Answers
Answer:
A and B do (1/10)th of the work in 1 day.
B and C do (1/15)th of the work in 1 day.
C and A do (1/20)th of the work in 1 day.
2A+2B+2C = (1/10)+(1/15)+(1/20)
= (6/60)+(4/60)+(3/60)
= 13/60
Or A, B and C do 13/120th of the work in 1 day.
C alone does (13/120)-(1/10) = (13/120)-(12/120) = 1/120th of the work in 1 day.
In the first 6 days that A, B and C worked together they did (6*13/120) or (13/20)th of the work. The work remaining after the first 6 days = (7/20)th.
Over the next 4 days, B and C do (4/15)th. The work completed after the first 10 days = (13/20)+(4/15) or (39/60)+(16/60) = 55/60. The work remaining after the first 10 days is (5/60) or (1/12)th.
C alone complete the remaining (1/12)th of the work in (1/12)/(1/120) = 10 days.
Step-by-step explanation: