# Time and Work FOR SSC,UPSC,APPSC for all govt Exams

Time and work Problems can be solved in Two ways

• Percentage Method
• LCM Method
LCM method is easier to use so will practice by LCM method

### Model-1

#### 1.A alone can finish work in 12 days and B alone can finish the same work in 24 days. then in how many days can A and B together will finish same Work?

Ans)

A=12 days                                                       A+B=?
B=24 days

Now take the LCM of A and B because we need find out A+B
So LCM of A and B is =24 it means Total work is 24 Units

Now we can find one days work for A and B Seperately

#### A=(Total number of units/No of Days)

=(24/12)
=2 units/day

#### B=(Total number of units/No of Days)

=(12/12)
= 1 Unit/day

So that A+B’s One day’s Work= 2+1
=3 units / Day
•           A and B together will finish same Work=(Total no.of Units/(No.of units/day))
=24/3
=  8 Days required to complete same job

#### 2.A and B can do a piece of Work in 12 days. While B alone can finish it in 30 days then A alone finish the work in?

Ans)

A+B=12 days                                                       A=?
B=30 days

Now take the LCM of (A+B) and B because we need find out A
So LCM of A and B is =24 it means Total work is 60 Units

Now we can find one days work for (A+B) and B Seperately

#### A+B=(Total number of units/No of Days)

=(60/12)
=5 units/day

#### B=(Total number of units/No of Days)

=(60/30)
= 2 Unit/day

So that B’s One day’s Work= ((A+B)’s work-A’s Work)  = (5-3)
=3 units / Day
•          B alone can finish same Work=(Total no.of Units/(No.of units/day))
=60/3
=  20 Days required to complete same job