Quantitative Aptitude

Time and Work

2,195 Questions
All Pairwise rates and staged schedules 440 Workers-days-hours chain rule 439 LCM units and efficiency ratios 409 Different worker categories 311 Combined rates and an unknown worker 257 Division of wages 219 Alternate work 110 Opposing rates 10

Time and Work Questions

Multiple choice

Veer is 40% less efficient than Bhavya and both complete the work together in 30 days, if Abhishek takes 10 days less as Veer and Bhavya takes together. Then find how many days will be required to complete the work, if all three work together?

  1. (a) 16 days

  2. (b) 12 days

  3. (c) 10 days

  4. (d) 8 days

  5. (e) 18 days
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Let Bhavya's efficiency be B. Veer's efficiency is 0.6B. Together they complete work in 30 days, so total work is 30 * 1.6B = 48B. Veer takes 48B / 0.6B = 80 days. Bhavya takes 48B / B = 48 days. Abhishek takes 48 - 10 = 38 days. The calculation for all three working together results in 12 days.

Multiple choice

P and Q together can do a job in 6 days. Q and R together can finish the same job in 60/7 days. P started the work and worked for 3 days. After that Q and R together worked for 6 days and completed the job. Find the difference between number of days taken by R alone and number of days taken by P alone to complete the job?

  1. a)10 days

  2. b)8 days

  3. c)12 days

  4. d)15 days

  5. e)None of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

P+Q=1/6, Q+R=7/60. P(3) + (Q+R)(6) = 1 => 3P + 6(7/60) = 1 => 3P + 0.7 = 1 => 3P = 0.3 => P = 0.1 (10 days). Q = 1/6 - 1/10 = 1/15. R = 7/60 - 1/15 = 3/60 = 1/20 (20 days). Difference = 20 - 10 = 10 days.

Multiple choice

2 men and 3 women can complete a piece of work in 20 days while 3 men and 2 women can complete the same work in 16 days. Find out in how many days 2 men and 1 woman can complete the same work?

  1. (a) 24 days

  2. (b) 25 days

  3. (c) 26 days

  4. (d) 27 days

  5. (e) 28 days
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

2M + 3W = 1/20, 3M + 2W = 1/16. Solving these: 6M + 9W = 3/20, 6M + 4W = 2/16. 5W = 3/20 - 1/8 = (6-5)/40 = 1/40. W = 1/200. M = (1/20 - 3/200) / 2 = 7/400. 2M + 1W = 14/400 + 2/400 = 16/400 = 1/25. Time = 25 days.

Multiple choice

Ajay and Vijay undertake to do a piece of work for Rs 200. Ajay alone can do it in 24 days while Vijay alone can do it in 30 days. With the help of Pradeep, they finish the work in 12 days. How much should Pradeep get for his work?

  1. Rs 20

  2. Rs 100

  3. Rs 180

  4. Rs 50
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Ajay's rate is 1/24, Vijay's is 1/30. Together they do 1/24 + 1/30 = 5/120 + 4/120 = 9/120 = 3/40 per day. With Pradeep, they do 1/12 per day. Pradeep's contribution is 1/12 - 3/40 = 10/120 - 9/120 = 1/120 per day. In 12 days, Pradeep does 12 * 1/120 = 1/10 of the work. His share is 1/10 * 200 = 20.

Multiple choice

A can do some work in 24 days, B can do it in 32 days and C can do it in 60 days. They start working together. A left after 6 days and B left after working for 8 days. How many more days are required to complete the whole work?

  1. 30

  2. 25

  3. 22

  4. 20
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Work rates: A=1/24, B=1/32, C=1/60. In 6 days, A+B+C do 6*(1/24+1/32+1/60) = 6*(10+7.5+4)/240 = 6*(21.5/240) = 129/240. In next 2 days, B+C do 2*(1/32+1/60) = 2*(15+8)/480 = 46/480 = 23/240. Total work done = 129/240 + 23/240 = 152/240. Remaining work = 88/240. C does this in (88/240) / (1/60) = 88/4 = 22 days.

Multiple choice

X and Y can complete a job separately in 40 and 60 days. After working together for 8 days, X leaves. What is the total time in which the work is completed?

  1. 48 days

  2. 44 days

  3. 46 days

  4. 40 days

  5. None of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

X's rate = 1/40, Y's rate = 1/60. Together rate = 1/40 + 1/60 = 5/120 = 1/24. Work done in 8 days = 8/24 = 1/3. Remaining work = 2/3. Y completes 2/3 at rate 1/60, time = (2/3) * 60 = 40 days. Total time = 8 + 40 = 48 days.

Multiple choice

Dev and Tukku can do a piece of work in 45 and 40 days respectively. They began the work together, but Dev leaves after some days and Tukku finished the remaining work in 23 days. After how many days did Dev leave?

  1. 7 days

  2. 8 days

  3. 9 days

  4. 11 days
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Let Dev work for x days. Dev's daily work is 1/45, Tukku's is 1/40. Tukku worked for (x + 23) days total. The equation is x/45 + (x + 23)/40 = 1. Multiplying by 360 gives 8x + 9(x + 23) = 360, so 17x + 207 = 360, 17x = 153, x = 9.

Multiple choice

B is twice efficient as A and A can do a piece of work in 15 days. A started the work andafter a few days B joined him. They completed the work in 11 days, from the starting. Forhow many days did they work together?

  1. 1 day

  2. 3 day

  3. 2 days

  4. 4 days

  5. 5 days
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

A's efficiency = 1/15. B's efficiency = 2/15. Let x be days worked together. A works 11 days, B works x days. (11/15) + (2x/15) = 1. 11 + 2x = 15. 2x = 4. x = 2 days.