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.
Ans plz
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.
solve in short cut way
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