A and B work in 12 days B and C can do 15 days and C and A can do in 20 days. A can do alone work in which day
Answers
In 1 day A and B together do=1/12 part of the work.
In 1 day B and C together do=1/15 part of the work
In 1 day A and C together do=1/20 part of the work
In 1 day A,B and C together do = {(1/12)+(1/15)+(1/20)}*1/2
= {(5+4+3)/60}*1/2
= (12/60)*1/2
= (1/5)*1/2
= 1/10 part of the work
In 1 day A alone does = {(1/10)-(1/15)}
= {(3-2)/30}
= 1/30 part of the work
1/30 part of the work is completed in 1 day
So, 1 part of the work is completed in={1/(1/30)}
= {(1*30)/1}
= 30 days
(Ans): A alone does the work in 30 days.