Time and Work Tips and Tricks .
Time and work aptitude questions are asked in every competitive exam.This section will provide shortcuts, tips and tricks to solve quantitative aptitude questions on time and work. These are similar to time and distance shortcuts or ratio and proportion shortcuts. So, all you have to do is be thorough with the basics and practice as many questions as you can.
To make the chapter easy for you all, we are providing you all some Important Short Tricks to Time & Work Questions which will surely make the chapter easy for you all.
Mantra to Crack Time and Work Questions
1. Work from Days:
If A can do a piece of work in n days, then A’s n days work is=1/n
No. of days = total work / work done in 1 day
Days from Work: If A’s 1 day’s work =1/n then A can finish the work in n days.
2. Relationship between Men and Work.
More men ——- can do ——-> More work
Less men ——- can do ——-> Less work
3. Relationship between Work and Time
More work ——– takes——> More Time
Less work ——– takes——> Less Time
4. Relationship between Men and Time
More men ——- can do in ——-> Less Time
Less men ——- can do in ——-> More Time
5. If M1 persons can do W1 work in D1 days and M2 persons can do W2 work in D2 days, then
6. If M1 persons can do W1 work in D1 days for h1 hours and M2 persons can do W2 work in D2 days for h2 hours, then
7. If A can do a work in ‘x’ days and B can do the same work in ‘y’ days, then the number of days required to complete the work if A and B work together is
8. If A can do a work in ‘x’ days and A + B can do the same work in ‘y’ days, then the number of days required to complete the work if B works alone is
Sample Questions –
1. Shambhu is twice as good as workman as Bablu and together they finish a piece of work in 18 days. Find the total number of days in which Bablu can finish the work.
a) 27 days
b) 54 days
c) 56 days
d) 68 days
Answer: Option B
Explanation:- As per question, Shambhu does twice the work as done by Bablu. So A:B = 2:1. Also (Shambhu+Bablu) one day work is 1/18
To get days in which Bablu will finish the work, lets calculate work done by Bablu in 1 day =(118 ∗13 )=154. So Bablu will complete the work in 54 days
2. Ritu can complete a piece of work in 5 days, but with the help of her son she can do it in 3 days. Find the time taken by the son alone to complete the work.
a) 7.5 days
b) 13 days
c) 11 days
d) 9 days
Answer: Option A
Explanation:- In this type of question, where we have one person work and together work done. Then we can easily get the other person work just by subtracting them. As,
Son’s one day work = (1/3 −1/5 )=(5−3/15 )=2/15
So son will do whole work in 2/15 days
which is = 7.5 days
3. Two pipes can fill the cistern in 10 hr and 12 hr respectively, while the third pipe can empty it in 20 hr. Simultaneously, if all the pipes are opened then the cistern will be filled in
a) 7.5 hr
b) 8 hr
c) 5 hr
d) 10 hr
Answer – (A)
Explanation:- Work done by all the tanks working together in 1 hour.
⇒ 1/10+1/12-1/20=2/15. Hence, tank will be filled in 15/2= 7.5 hour.
4. Mr. Chawla is on tour and he has Rs 360 for his expenses. If he exceeds his tour by 4 days he must cut down daily expenses by Rs 3. The number of days of Mr. Chawla’s tour programme is
a) 28 Days
b) 24 Days
c) 22 Days
d) 20 Days
Answer – (D)
Explanation:- Let Mr. Chawla under takes a tour of x days.
Then, expenses for each day =360/x
⇒ x=20 and −24
Hence, x= 20 days.