Time & Work

Treat the job as one whole. If A finishes it in a days, A does 1/a of it each day, and the daily shares of people working together simply add.

🎯 Try it yourself

Tap an answer. You'll see if it's right, and why. Easy ones come first.

1. Q1Easy

   7 workers build a wall in 16 days. How many days will 16 workers take?

   1. A7
   2. B10
   3. C8
   4. D11
   Show answer

   Answer: A. 7

   💡 Total work = 7 × 16 = 112 man-days, and 112 ÷ 16 = 7 days.

2. Q2Easy

   21 workers build a wall in 12 days. How many days will 7 workers take?

   1. A4
   2. B26
   3. C37
   4. D36
   Show answer

   Answer: D. 36

   💡 Total work = 21 × 12 = 252 man-days, and 252 ÷ 7 = 36 days.

3. Q3Easy

   9 men harvest a field in 10 days. How many days for 6 men?

   1. A15
   2. B13
   3. C16
   4. D18
   Show answer

   Answer: A. 15

   💡 Total work = 9 × 10 = 90 man-days, and 90 ÷ 6 = 15 days.

4. Q4Medium

   Varun paints a wall in 18 days; Kavya paints it in 63 days. Days together?

   1. A14
   2. B45
   3. C15
   4. D40
   Show answer

   Answer: A. 14

   💡 Together they do 1/18 + 1/63 = 1/14 of the work a day, so 14 days.

5. Q5Medium

   Farhan does a job in 6 days and Nisha in 12 days. Days taken together?

   1. A3
   2. B4
   3. C8
   4. D9
   Show answer

   Answer: B. 4

   💡 Together they do 1/6 + 1/12 = 1/4 of the work a day, so 4 days.

6. Q6Medium

   Nikhil does a job in 8 days and Simran in 24 days. Days taken together?

   1. A16
   2. B6
   3. C8
   4. D5
   Show answer

   Answer: B. 6

   💡 Together they do 1/8 + 1/24 = 1/6 of the work a day, so 6 days.

7. Q7Hard

   Nikhil and Jaya together take 7 days; Nikhil alone takes 8 days. Days for Jaya alone?

   1. A1
   2. B56
   3. C63
   4. D15
   Show answer

   Answer: B. 56

   💡 Jaya's share a day = 1/7 − 1/8 = 1/56, so 56 days.

8. Q8Hard

   Karan works 3 times as fast as Kavya. Together they take 12 days. Days for Kavya alone?

   1. A48
   2. B58
   3. C84
   4. D50
   Show answer

   Answer: A. 48

   💡 If Kavya does 1 part a day, Karan does 3, so together 4 parts a day. The job is 4 × 12 = 48 parts, so Kavya alone needs 48 days.