Aptitude - Time and Work - Discussion
Discussion Forum : Time and Work - General Questions (Q.No. 10)
10.
A machine P can print one lakh books in 8 hours, machine Q can print the same number of books in 10 hours while machine R can print them in 12 hours. All the machines are started at 9 A.M. while machine P is closed at 11 A.M. and the remaining two machines complete work. Approximately at what time will the work (to print one lakh books) be finished ?
Answer: Option
Explanation:
| (P + Q + R)'s 1 hour's work = |  |
1 | + | 1 | + | 1 |  |
= | 37 | . |
| 8 | 10 | 12 | 120 |
| Work done by P, Q and R in 2 hours = | |
37 | x 2 | |
= | 37 | . |
| 120 | 60 |
| Remaining work = | |
1 - | 37 | |
= | 23 | . |
| 60 | 60 |
| (Q + R)'s 1 hour's work = | |
1 | + | 1 | |
= | 11 | . |
| 10 | 12 | 60 |
| Now, | 11 | work is done by Q and R in 1 hour. |
| 60 |
| So, | 23 | work will be done by Q and R in | |
60 | x | 23 | |
= | 23 | hours  2 hours. |
| 60 | 11 | 60 | 11 |
So, the work will be finished approximately 2 hours after 11 A.M., i.e., around 1 P.M.
Discussion:
95 comments Page 9 of 10.
Gautham Raj said:
9 years ago
It's very clear now thank you all for explaining this.
Sneha said:
1 decade ago
Can you please explain how 1/8+1/10+1/12= 37/120.
Vachu said:
1 decade ago
Why p is working for two hrs its ont mentioned?
Pranot said:
6 years ago
Why we are subtracting 1-37/60? please explain.
Sparton said:
1 decade ago
Nice methods explains above thank you friends.
Sojib said:
9 years ago
Can anyone give an easy and simple solution?
Keval shah said:
1 year ago
Thanks for the explanation @Sai Vinitha.
(2)
Syed said:
1 decade ago
Can some one tell me why 1-37/60 ?
Res said:
10 years ago
How you consider 1hr for (Q + R).
Sudharshan said:
9 years ago
I didn't understand @Sukanya.
Post your comments here:
Quick links
Quantitative Aptitude
Verbal (English)
Reasoning
Programming
Interview
Placement Papers