A and B can do a piece of work in 40 days, B and C can do it in 120 days. If B alone can do it in 180 days, in how many days will A and C do it together?

A + B takes 40 days. B alone takes 180 days.
∴ A will take 1/40 – 1/180 = 7/360 ⇒ 360/7 days.
B + C takes 120 days.
∴ C alone will take 1/120 – 1/180 = 1/360 i.e. 360 days.
∴ A & C together will take 7/360 + 1/360= 8/360
⇒ 360/8 = 45 days to complete the work.

A + B takes 40 days. B alone takes 180 days.
∴ A will take 1/40 – 1/180 = 7/360 ⇒ 360/7 days.
B + C takes 120 days.
∴ C alone will take 1/120 – 1/180 = 1/360 i.e. 360 days.
∴ A & C together will take 7/360 + 1/360= 8/360
⇒ 360/8 = 45 days to complete the work.

Loparani says

Ans plz

Saran Harika says

A + B takes 40 days. B alone takes 180 days.

∴ A will take 1/40 – 1/180 = 7/360 ⇒ 360/7 days.

B + C takes 120 days.

∴ C alone will take 1/120 – 1/180 = 1/360 i.e. 360 days.

∴ A & C together will take 7/360 + 1/360= 8/360

⇒ 360/8 = 45 days to complete the work.

bhavani shankar says

solve in short cut way

Vamsi says

there is no any other shortcut for this question.do practice more and more then you will find some technique in your own way