Raju can do 25% of a piece of work in 5 days. How many days will he take to complete the work ten times?
He will complete the work in 20 days. Hence, he will complete ten times the work in 200 days.
Nishu and Archana can do a piece of work in 10 days and Nishu alone can do it in 12 days. In how many days can Archana do it alone?
N + A = 10%
N = 8.33%
Hence A = 1.66% Æ 60 days.
If 8 boys and 12 women can do a piece of work in 25 days, in how many days can the work bedone by 6 boys and 11 women working together?
The data is insufficient, since we only know that the work gets completed in 200 boy days and 300 women days.
A can do a piece of work in 20 days. He works at it for 5 days and then B finishes it in 10 moredays. In how many days will A and B together finish the work?
In 5 days, A would do 25% of the work. Since, B finishes the remaining 75% work in 10 days, we
can conclude that B’s work in a day = 7.5%
Thus, (A + B) = 12.5% per day.
Together they would take 100/12.5 = 8 days.
Twenty workers can finish a piece of work in 30 days. After how many days should 5 workers leave the job so that the work is completed in 35 days?
Total man days required = 600 man days. If 5 workers leave the job after ‘n’ days, the total work
would be done in 35 days. We have to find the value of ‘n’ to satisfy:
20 × n + (35 – n) × 15 = 600.
Solving for n, we get
20n – 15n + 35 × 15 = 600
5n = 75
n = 15.
Subhash can copy 50 pages in 10 hours; Subhash and Prakash together can copy 300 pages in 40hours. In how much time can Prakash copy 30 pages?
Subhash can copy 200 pages in 40 hours (reaction to the first sentence). Hence, Prakash can copy
100 pages in 40 hours. Thus, he can copy 30 pages in 30% of the time: i.e. 12 hours.
Sashi can do a piece of work in 25 days and Rishi can do it in 20 days. They work for 5 days and then Sashi goes away. In how many more days will Rishi finish the work?
Sashi = 4%, Rishi = 5%. In five days, they do a total of 45% work. Rishi will finish the remaining
55% work in 11 more days.
Manoj takes twice as much time as Anjay and thrice as much as Vijay to finish a piece of work.Together they finish the work in 1 day. What is the time taken by Manoj to finish the work?
Let Anjay take 3t days, Vijay take 2t days and Manoj take 6t days in order to complete the work.
Then we get:
1/3t + 1/2t + 1/6t = 1 Æ t = 1. Thus, Manoj would take 6t = 6 days to complete the work.
Raju is twice as good as Vijay. Together, they finish the work in 14 days. In how many days can Vijay alone do the same work?
Raju being twice as good a workman as Vijay, you can solve the following equation to get the
1/R + 1/2R = 1/14.
Solving will give you that Vijay takes 42 days.
If 12 men and 16 boys can do a piece of work in 5 days and 13 men and 24 boys can do it in 4days, compare the daily work done by a man with that done by a boy?
12 × 5 man days + 16 × 5 Boy days
= 13 × 4 man days + 24 × 4 Boy days
Æ 8 man days = 16 Boy days
1 man day = 2 Boy days.
Required ratio of man’s work to boy’s work = 2 : 1.
30 men working 5 h a day can do a work in 16 days. In how many days will 20 men working 6 h a day do the same work?
Work equivalence method:
30 × 5 × 16 = 20 × 6 × n
Gives the value of n as 20 days
15 men could finish a piece of work in 210 days. But at the end of 100 days, 15 additional men are employed. In how many more days will the work be complete?
Total work = 15 × 210 = 3150 man days.
After 100 days, work done = 15 × 100 = 1500 man days.
Work left = 3150 – 1500 = 1650 man days.
This work has to be done with 30 men working each day.
The number of days (more) required = 1650/30 = 55 days.
In a fort there was sufficient food for 200 soldiers for 31 days. After 27 days 120 soldiers left the fort. For how many extra days will the rest of the food last for the remaining soldiers?
After 27 days, food left = 4 × 200 = 800 soldier days worth of food. Since, now there are only 80
soldiers, this food would last for 800/80 = 10 days. Number of extra days for which the food lasts
= 10 – 4 = 6 days.
Ajay and Vijay can do a piece of work in 28 days. With the help of Manoj, they can finish it in 21days. How long will Manoj take to finish the work all alone?
Ajay + Vijay = 1/28 and Ajay + Vijay + Manoj = 1/21.
Hence, Manoj = 1/21 – 1/28 = 1/84.
Hence, Manoj will take 84 days to do the work.
Ajay and Vijay together can do a piece of work in 6 days. Ajay alone does it in 10 days. What time does Vijay require to do it alone?
A + V = 16.66% and A = 10% Æ V = 6.66%. Consequently Vijay would require 100/6.66 = 15
days to do it alone.