Time and Work MCQ Quiz - Objective Question with Answer for Time and Work - Download Free PDF
Last updated on Apr 21, 2025
Latest Time and Work MCQ Objective Questions
Time and Work Question 1:
Tom can alone complete the work in 8 days while Tom & Jerry together can complete the same work in 2(2/3) days. Find the number of days required by Jerry alone to complete double work.
Answer (Detailed Solution Below)
Time and Work Question 1 Detailed Solution
Given:
Tom can complete the work in 8 days.
Tom and Jerry together can complete the work in 2(2/3) days.
Calculation:
Total work = LCM( 8, 8/3) = 8 units
Efficiency of Tom = 8/8 = 1 unit per day
Efficiency of Tom and Jerry = (8 × 3)/8 = 3 unit per day
Efficiency of Jerry = 3 - 1 = 2 unit per day
Double work = 8 × 2 = 16 units
Days required by Jerry alone to complete double work = 16/2 = 8 days
∴ Option 3 is the correct answer.
Time and Work Question 2:
Three flexible pipes that can serve as inlet as well as outlet pipes have been attached to a tank. The rates of filling or emptying the tank by these three pipes are in the ratio 1 : 2 : 3. The largest pipe can alone fill the empty tank in 8 hours. Initially the tank is full and the three pipes were used as outlet pipes for ‘T’ hours. After the tank is emptied, later the smallest pipe alone filled the entire tank in 24 hours. Find the value of ‘T’.
Answer (Detailed Solution Below)
Time and Work Question 2 Detailed Solution
Explanation:
Let the capacity of the three pipes be x, 2x and 3x litres per hour.
As the largest pipe fills the empty tank in 7 hours, capacity of the tank = 8 × 3x = 24x
The smallest pipe took 24 hours to fill the tank. Therefore, it has filled the empty tank.
i.e., the three pipes must have emptied the tank.
Time taken to empty the tank = \(\frac{24x}{x+2x+3x}=4.\)
Answer: 4 hrs.
Time and Work Question 3:
A can complete a work in [x + 4] days and B alone complete the work in [x – 2] days. Ratio of efficiency of A and B is 3:4. C can alone complete the work in [x + 10] days. Find in how many days A, B and C complete the total work?
Answer (Detailed Solution Below)
Time and Work Question 3 Detailed Solution
Calculation
Ratio of efficiency of A and B is 3:4
So, we can say, [x + 4] / [x – 2] = 4/3
Or, 3x + 12 = 4x – 8
Or, x = 20
A, B and C complete the work alone in 24, 18 and 30 days respectively.
Total work = LCM of 24 , 18 and 30 = 360
So, Efficiency of A, B and C is 15, 20 and 12 respectively.
Required time = [360 / 47] days
Time and Work Question 4:
Two pipes A and B can fill the tank in 40 and 60 minutes, respectively. Both the pipes are opened together. After how many minutes should the pipe B be turned off, so that the tank be fill in 30 minutes?
Answer (Detailed Solution Below)
Time and Work Question 4 Detailed Solution
Given:
Pipe A fills the tank in 40 minutes.
Pipe B fills the tank in 60 minutes.
Total time to fill the tank = 30 minutes.
Formula used:
LCM of 40 and 60.
Work done = Efficiency × Time.
Calculations:
LCM of 40 and 60 = 120 (Total capacity of the tank).
Efficiency of pipe A = 120 / 40 = 3 units/minute.
Efficiency of pipe B = 120 / 60 = 2 units/minute.
Let pipe B be turned off after x minutes.
Pipe A works for 30 minutes.
Pipe B works for x minutes.
Work done by A in 30 minutes = 3 × 30 = 90 units.
Work done by B in x minutes = 2 × x = 2x units.
Total work done = 90 + 2x = 120.
⇒ 2x = 120 - 90.
⇒ 2x = 30.
⇒ x = 30 / 2.
⇒ x = 15.
∴ Pipe B should be turned off after 15 minutes.
Time and Work Question 5:
A and B can do a piece of work in 43 days and 3 days, respectively. The number of days [Correct to one decimal place] required to complete the work if both A and B work together is:
Answer (Detailed Solution Below)
Time and Work Question 5 Detailed Solution
Given:
A can do the work in 43 days
B can do the work in 3 days
Formula used:
Time taken to complete work together = LCM of individual times
Calculation:
Total work = LCM of 43 and 3 = 129 (since 43 and 3 are co-prime)
Efficiency of A = 129/43 = 3
Efficiency of B = 129/3 = 43
Therefore, the number of days to complete the work = 129 / 46 = 2.80 days
∴ The number of days required to complete the work together = 2.8 days
Top Time and Work MCQ Objective Questions
A cistern has two pipes one can fill it with water in 16 hours and other can empty it in 10 hours. In how many hours will the cistern be emptied if both the pipes are opened together when 1/5th of the cistern is already filled with water?
Answer (Detailed Solution Below)
Time and Work Question 6 Detailed Solution
Download Solution PDFShortcut Trick
If both pipes are open, total efficiency = (A + B) = 5 + (-8) = -3 units
According to question,
Amount of water in the tank = (1/5) × 80 = 16 units
Time taken to empty the tank = work/efficiency = 16/((-3)) = 5.33 hours
Alternate Method
GIVEN :
Time by which pipe A can fill the tank = 16 hours
Time by which pipe B can empty the tank = 10 hours
The cistern is (1/5)th full.
CONCEPT :
Total work = time × efficiency
CALCULATION :
| Work | Time | Efficiency |
| A | 16 | 80/16 = 5 |
| B | 10 | 80/10 = (-8) |
|
total work (LCM) |
80 |
Negative efficiency indicates pipe B is emptying the tank.
If both pipes are open, total efficiency = (A + B) = 5 + (-8) = -3 units
From the total efficiency it is clear that when both are opened, the tank is being emptied.
Amount of water in the tank = (1/5) × 80 = 16 units
The water level will not rise as the total action is emptying when both are opened together.
Time taken to empty the tank = work/efficiency = 16/((-3)) = 5.33 hours
∴ Time taken to empty the tank is 5.33 hours.
A and B together can do a piece of work in 50 days. If A is 40% less efficient than B, in how many days can A working alone complete 60% of the work?
Answer (Detailed Solution Below)
Time and Work Question 7 Detailed Solution
Download Solution PDFGiven:
A and B together can do a piece of work in 50 days.
A is 40% less efficient than B
Concept used:
Total work = Efficiency of the workers × time taken by them
Calculation:
Let the efficiency of B be 5a
So, efficiency of A = 5a × 60%
⇒ 3a
So, total efficiency of them = 8a
Total work = 8a × 50
⇒ 400a
Now,
60% of the work = 400a × 60%
⇒ 240a
Now,
Required time = 240a/3a
⇒ 80 days
∴ A can complete 60% of the work working alone in 80 days.
Shortcut Trick
We know 40% = 2/5, Efficiency of B = 5 and A = 3
So, Total work = (5 + 3) × 50 = 400 units
So, 60% of the total work = 60% of 400 = 240 units
So A alone can do the work in 240/3 = 80 days
A can finish a work in 15 days, B can finish the same work in 25 days. They work together for 5 days. The rest of the work is finished by A and C in 4 days. Then C alone can finish the work in:
Answer (Detailed Solution Below)
Time and Work Question 8 Detailed Solution
Download Solution PDFGiven:
A can finish in 15 days, B can finish it in 25 days.
They work together for 5 days.
Concept used:
Efficiency = (Total work / Total time taken)
Efficiency = work done in a single day
Calculation:
Let total work be 75 units ( LCM of 15 and 25 is 75)
The efficiency of A
⇒ 75 /15 = 5 units
The efficiency of B
⇒ 75 / 25 = 3 units
The efficiency of A+B,
⇒ (5 + 3) units = 8 units
In 5 days total work done is 8 × 5 = 40 units
Remaining work 75 - 40 = 35 units
In the last 4 days, A does 4 × 5 = 20 units
Remaining work 35 - 20 = 15 units done by C in 4 days
So C does 75 units in (75 / 15) × 4 = 20 days
∴ The correct option is 3
Harish and Bimal can complete a task in 20 days. They worked at it for 15 days and then Bimal left. The remaining work was done by Harish alone, in 10 days. Harish alone can complete the entire task in:
Answer (Detailed Solution Below)
Time and Work Question 9 Detailed Solution
Download Solution PDFGiven:
No of days taken by Harish and Bimal = 20
Formula used:
No of days taken = Work/Efficiency
Calculation:
Let the total work be = 1
One day work done by Harish and Bimal = 1/20
Work done by Harish and Bimal in 15 days = 1/20 × 15 = 3/4
⇒ Remaining work = 1 - 3/4 = 1/4
Harish did remaining work in 10 days alone.
⇒ One day work done by Harish = 1/4 ÷ 10 = 1/40
∴ Time taken by Harish to do the entire task alone = 1 ÷ 1/40 = 40 days
Shortcut TrickFraction of work done by Harish & Bimal in 15 days = 15/20 = 3/4
The remaining 1/4th (25%) of work was done by Harish in 10 days.
∴ The 100% work would be done by Harish in (10 × 4) 40 days.
23 people could do a piece of work in 18 days. After 6 days 8 of the workers left. How many days from then will it take to complete the work?
Answer (Detailed Solution Below)
Time and Work Question 10 Detailed Solution
Download Solution PDFGiven:
23 people could do a piece of work in 18 days.
After 6 days 8 of the workers left.
Concept used:
Total work = Men needed × Days needed to finish it entirely
Calculation:
Total work = 23 × 18 = 414 units
In 6 days, total work done = 23 × 6 = 138 units
Remaining work = (414 - 138) = 276 units
Time taken to complete the remaining work = 276 ÷ (23 - 8) = 18.4 days
∴ 18.4 days it will take to finish the work.
Two pipes, when working one at a time, can fill a cistern in 3 hours and 4 hours, respectively while a third pipe can drain the cistern empty in 8 hours. All the three pipes were opened together when the cistern was 1/12 full. How long did it take for the cistern to be completely full?
Answer (Detailed Solution Below)
Time and Work Question 11 Detailed Solution
Download Solution PDFGiven:
First pipe can fill the cistern = 3 hours
Second pipe can fill the cistern = 4 hours
Third pipe can drain the cistern = 8 hours
Calculation:
Let the total amount of work in filling a cistern be 24 units. (LCM of 3, 4 and 8)
Work done by pipe 1 in 1 hour = 24/3 = 8 units.
Work done by pipe 2 in 1 hour = 24/4 = 6 units.
Work done by pipe 3 in 1 hour = 24/ (-8) = -3 units
Total work done in 1 hour = 8 + 6 – 3 = 11 units
The time required to complete 11/12th of the work = 11/12 × 24/ 11 = 2 hours
∴ The correct answer is 2 hours.
The efficiency of A, B, and C is 2 : 3 : 5. A alone can complete a work in 50 days. They all work together for 5 days and then C left the work, in how many days A and B together can complete the remaining work?
Answer (Detailed Solution Below)
Time and Work Question 12 Detailed Solution
Download Solution PDFGiven:
Efficiency of A, B and C = 2 : 3 : 5
A alone can complete the work in = 50 days
Formula:
Total work = Efficiency × Time
Calculation:
Let efficiency of A be 2 units/day
Efficiency of A, B and C = 2 : 3 : 5
Total work = 2 × 50 = 100 units
Work done by A, B and C in 5 days = (2 + 3 + 5) × 5 = 10 × 5 = 50 units
Remaining work = 100 – 50 = 50 units
∴ Time taken by A and B to complete the remaining work = 50/(2 + 3) = 50/5 = 10 days
A and B together are supposed to do 13/15 of the work and B and C together 11/20 of the work. If the difference between wages of A and C is Rs. 7600, then the total wages of A and C is:
Answer (Detailed Solution Below)
Time and Work Question 13 Detailed Solution
Download Solution PDFGiven:
Difference between wages of A and C = Rs. 7600
Formula Used:
Share in wages = Work done/Total work × Total wages
Calculation:
Let total work be 60 unit,
Work done by A and B = 13/15 × 60 = 52 unit
⇒ Work done by C = 60 – 52 = 8 unit
Work done by B and C = 11/20 × 60 = 33 unit
⇒ Work done by A = 60 – 33 = 27 unit
Work done by B = 60 – 27 – 8 = 25 unit
According to the question,
27 – 8 = 19 unit = 7600
⇒ 1 unit = 400
Total wages of A and C = (27 + 8) = 35 units = 35 × 400 = Rs. 14000
A,B and C can do a piece of work in 30 days, 40 days and 50 days, respectively. Beginning with A, if A, B and C do the work alternatively then in how many days will the work be finished?
Answer (Detailed Solution Below)
Time and Work Question 14 Detailed Solution
Download Solution PDFGiven:
A can do a piece of work = 30 days
B can do a piece of work = 40 days
C can do a piece of work = 50 days
Formula used:
Total work = efficiency × time
Calculation:
| Efficiency | Person | Time | Total work |
| 20 | A | 30 | 600 |
| 15 | B | 40 | |
| 12 | C | 50 |
According to the question:
⇒ (20 + 15 + 12) = 47 units = 3 days
⇒ 47 × 12 = 564 units = 3 × 12 = 36 days
⇒ (564 + 20 + 15) = 599 units = 38 days
Total work = 600 units = 38 + (1/12) = 38\(1\over12\) days.
∴ The correct answer is 38\(1\over12\) days.
If 'A' is 6 times more efficient than 'B', 'B' takes 32 days to complete the task, then find the number of days required to finish the whole work by 'A' and 'B' working together.
Answer (Detailed Solution Below)
Time and Work Question 15 Detailed Solution
Download Solution PDFGiven:
A is 6 times more efficient than B, & B takes 32 days to complete the task.
Formula used:
Total work = Efficiency × Time taken
Calculation:
A is 6 times more efficient than B
Efficiency of A ∶ Efficiency of B = 7 ∶ 1
Total work = Efficiency of B × Time taken
⇒ 1 × 32 = 32 units
Number of days required to finish the whole work by (A + B) = Total work/Efficiency of (A+ B)
⇒ 32/8
⇒ 4
∴ The total number of days required to finish the whole work by (A + B) is 4 days.
There is a difference in "Efficient" and " More efficient"
A is 6 times efficient than B means if B is 1 then, A will be 6
A is 6 times more efficient than B means if B is 1 then, A will be (1 + 6) = 7
In the question, it is given that A is 6 times more efficient which means if B is 1, then A will (1 + 6) times = 7 times efficient
So, Total efficiency of A and B = (1 + 7) = 8 units/day
Time taken to complete the work together = 32/8 days
⇒ 4 days and this is the answer.