Time And Work

Concept of work and time

        It is assumed that , if a problem does a work in n days or a pipe fills a cistern or reservoir in n days in n days , then equal amount of work on each of those days i.e. work done in a day is equal to 1/n,
 Also, number of days to complete a work = 1/(work done in one day).

→Efficiency is inversely proportional to the time (i.e. number of days/minutes/hours etc.).

FUNDAMENTAL FORMULAE
       Let M1 men can complete W1 work in D1 days working H1  h per day and earns a wages  of  ₹ R1
Similarly , let M2 men can complete W2 work in D2 days working H2 h per days and earns a wages of ₹ R2
Then,


Efficiency problem:- 

   If a person A is twice as efficient as B in doing a certain work , then time taken by A is half the time taken by B to complete the work. i.e. the ratio of time taken by A and B to do the same piece of work is 1:2.
 →    If A is two times more efficient than B, then it implies that A is thrice as efficient as B or A does the same work as B in 1/3rd of the time.


Wage Problem:-

it two or more groups/companies working for some time in a work combinedly and there is a total wage paid for combined work . Then, wage of separate is calculated by using ratio and proportion method.

Pipes and Cisterns:-

 Pipes are connected to tank of reservoir or cisterns are used to fill the tank or empty to fill or empty the tank.

INLET:- A pipe or tap connected with a tank is called an inlet if it fills it.
OUTLET:- A pipe or a tap connected with a tank tank is called as outlet,if it empties it.

Solved Problem on Time and Work







 Here is the PDF of Above solved example 
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More problem on time and work
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Solution of practice sheet
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