# Tricks and Shortcut

**Work from Days:**

If A can do a piece of work in n days, then A's 1 day's work =

**Days from Work:**

If A's 1 day's work = , Then A can finish the work in n days.

**Ratio:**

If A is thrice as good a workman as B, then:

Ratio of work done by A and B = 3 : 1.

Ratio of times taken by A and B to finish a work = 1 : 3

**Efficiency or Money Distribution:**

If A can do a work in a days and B in b days, the ratio of the work done by A and B in the same time is b : a. Hence any amount earned by them should be distribution in this ratio only.

Also, remember

*(Man Ã— Day Ã— Hour Ã— 1/work) in one situation = (Man Ã— Day Ã— Hour Ã— 1/work) in another situation.*# Pipes & Cisterns

**Inlet:**A pipe connected with a tank or a cistern or a reservoir, that fills it, is known as an inlet.

**Outlet:**A pipe connected with a tank or cistern or reservoir, emptying it, is known as an outlet.

If a pipe can fill a tank in x hours, then:

part filled in 1 hour = .

If a pipe can empty a tank in y hours, then:

part emptied in 1 hour = .

If a pipe can fill a tank in x hours and another pipe can empty the full tank in y hours (where y > x), then on opening both the pipes, then

the net part filled in 1 hour = .

If a pipe can fill a tank in x hours and another pipe can empty the full tank in y hours (where y > x), then on opening both the pipes, then

the net part emptied in 1 hour = .

- When A can do work in a day and B can do work in b day then working together they complete work in day.
- When A can do work in a day and working together A and B in b day then B can complete work in day.
- When A can do work in a day and B can do work in b day C can do work in c day then working together they complete work in day.
- When A and B completed work in m day, B and C in n day C and A in p day then working together they complete work in day
- A alone Complete work in day
- B alone Complete work in day
- C alone Complete work in day