# Aptitude - Time and Work - Discussion

### Discussion :: Time and Work - General Questions (Q.No.18)

18.

Ravi and Kumar are working on an assignment. Ravi takes 6 hours to type 32 pages on a computer, while Kumar takes 5 hours to type 40 pages. How much time will they take, working together on two different computers to type an assignment of 110 pages?

 [A]. 7 hours 30 minutes [B]. 8 hours [C]. 8 hours 15 minutes [D]. 8 hours 25 minutes

Explanation:

 Number of pages typed by Ravi in 1 hour = 32 = 16 . 6 3

 Number of pages typed by Kumar in 1 hour = 40 = 8. 5

 Number of pages typed by both in 1 hour = 16 + 8 = 40 . 3 3

 Time taken by both to type 110 pages = 110 x 3 hours 40

 = 8 1 hours (or) 8 hours 15 minutes. 4

 Pandu said: (Jan 23, 2011) How to calculate the 8 1/4 hours= 8 hours 15 minutes.

 Mahesh said: (Feb 4, 2011) 1 hour mean 60 minutes 1/4 hour mean 15 minutes 1/2 hour = 30 minutes

 Mani said: (Apr 11, 2011) 33/4 8.25 0.25 *60 = 15

 Ramu said: (Sep 22, 2011) Why did they change 40/3 into 3/40 in the next line. ? They could have done like 110*(40/3) itself. !

 Ashwin said: (Oct 9, 2011) No of pages typed/Hours=40/3/1=40/3-----First case No of pages typed/Hours=110/x-----------second case The ratio would be same in both the cases 40/3=110/x Therefore x=110*3/40=8*1/4 hrs

 Navena said: (Apr 18, 2012) How do you solve 16/3+8 ?

 Kunu said: (Apr 27, 2012) @Navena 16/3+8= 16+24/3= 40/3(LCM 3)

 Krittika said: (Aug 31, 2012) Why can't I do like this? 32 pages r typed by Ravi in 6 hrs 1 page is typed in 6/32=3/16 hrs. similarly 1 page typed by kumar is 1/8 hrs. then 1 page typed by both of them in (3/16+1/8)=5/16 hrs. So 110 pages typed by them in 110 * 5/16 hrs = !!?

 Nitin. said: (Oct 12, 2012) If you solve 110*3/40 you will get exactly 8.25. Then why 8.15 please anyone explain in detail.

 Sunny said: (Feb 17, 2013) I did the following steps but the answer I am getting is 8.25: Ravi takes 6 hrs to type 32 pages. For one hour he will type:32/6=16/3 pages. Kumar takes 5 hrs to type 40 pages. For one hour he will type:40/5=8 pages. So,for one hour kumar and ravi type (16/3+5) pages i.e. 40/3. 1 hour---40/3 pages. ? ---110 pages. Do cross multiplication and you will get answer.

 Kishore said: (May 3, 2013) @Krittika. Your method is not correct. It can be explain with a simple example. Suppose ravi type 1 page in 1 hr. Kumar type type 1 page in 1.5 hr. If they work together, 1 page type by both can not be 1+1.5 = 2.5 hr (combined effort should reduce the time but here its opposite). I hope you get it.

 Amansamana said: (Aug 12, 2013) Hey guys why should direct count total unit, like, Ravi 6* 32 = 192. And kumar unit 5 * 40 = 200. But solving by that answer will be approximately 9, so anybody can tell, what is the mistake in that method?

 Sumit Vyas said: (Jun 28, 2014) (16/3+8) = 40/3 how can simplify this equation?

 Divya said: (Sep 16, 2014) @Kishore. Can you please explain your example in a detailed manner. How do you assume that ravi takes 1 hr to type 1 page and kumar takes 1.5 hrs to type 1 page.

 Anil said: (Jan 7, 2015) 1 hr = 60 minutes. 0.25 hr = x. Cross multiplication. 60*0.25 = 15.

 Mohammed Ashraf said: (Jan 11, 2015) Here is the easy step guys. No. of pages typed by Ravi in 6 hours = 32. Therefore no. of pages typed in 1 hr = 32/6 = 16/3. No. of pages typed by Kumar in 5 hr = 40. Therefore no. of pages typed in 1 hr = 40/5 = 8. No. of. pages typed together in 1 hr = (16/3+8) = 40/3. So, 40/3 pages were typed in 1 hr. Therefore 110 pages will be typed in 1*110/(40/3) (by cross multi). = 3 110*3/40 hours. Hope you will get it.

 Vivek said: (Jun 7, 2015) How will you get 8 1/4 when you multiply 110*3/40?

 Gnanamayil said: (Jul 1, 2015) K but one doubt if we take days or works in time and work we take like 5 days means we put 1/5 but here why we take directly without denominator like 8 as 8 not 1/8. Please explain me.

 Ranji said: (Oct 2, 2015) D is the option C is incorrect it comes as 8.25 hrs and not 8.15 hrs.

 Khoshali said: (Oct 9, 2015) Isn't 8.25 is the right answer? R: 1 hour = 32/6 pages. K: 1 hour = 40/5 pages. Let us assume they worked for x hours to complete the work. [32/6+40/5]x = 110. [160+240]x/30 = 110. 400x/30 = 110. x = 8.25.

 Pritam Kumar said: (Jan 18, 2016) Every step is correct till the last. Only calculation mistake is there. It's answer should be option D: 8 hours 25 minutes.

 Kaushal said: (Mar 17, 2016) Yes its answer should be D.

 Kumar Abhishek said: (May 7, 2016) How the answer is option C? The correct answer is 8 hours 25 minutes.

 Ankit said: (Jun 10, 2016) Yes, answer id 8 hours and 25 minutes. Because it is 33/4, which is equal to 8 * 1/4, not 8 + (1/4). Understand this point.

 Harsh said: (Jun 29, 2016) Assume that the both took X house to complete the job and from the question, we know that Ravi types (16/3) pages in an hour while kumar types 8 pages. So, ((16/3) * X + (8) * X) = 110. Solve to get X = 8.25. Where 0.25 of 1 hour is 15 mins, so, X = 8 hrs and 15 mins.

 Kavi said: (Jul 9, 2016) Here 3/40 * 110 is given 8.25. But we have the 0.25 value so it is converted to minutes 0. 25 * 60 = 15. So the answer becomes 8 hours 15 minutes. Thank you.

 Milon said: (Aug 14, 2016) Anybody know the quick method to solve this type of problem?

 Mahi said: (Aug 28, 2016) 33/4 = 8.25 not 8.15.

 Kalai said: (Sep 14, 2016) Yes, the right answer is 8.25mins.

 Kranthi said: (Oct 21, 2016) Answer 8.15 min. After all calculation, we get 8.25. Now 8 hours take beside, .25 = 25/100 = 1/4. If we convert 1/4 in min it's 15 min ( 1/4 * 60). Now answer 8.15 min.

 Abhi said: (Dec 16, 2016) Why 40/3 is taken as 3/40? Not getting this, please help me.

 Tara said: (Dec 31, 2016) @Ranji. The answer 8 hours and 15 minutes is CORRECT. The error you are overlooking is the number 0.25. In you answer, mathematically it comes to 8.25, yes, but remember that means 8 hours and 0.25 hours. 0.25 hours is basically a quarter of an hour which is 15 minutes.

 Arunkumar said: (Jan 27, 2017) Convert hr to min . Ravi's one min work = 32/360 = 4/45 (6 hours = 360 min). Kumar's one min work = 40/300 = 2/15 (5 hours = 300 min). 4/45 + 2/15 = 10/45( ravi + kumar one min work). So, for 110 pages 110(45/10) = 495 mins ==> 8 hrs(480 min) + 15 min ==> 8hrs 15 min.

 Vikas Baba said: (Jun 1, 2017) Please, tell me that why we not required of remaining work = 1-40/3 =37/3?

 Lieja said: (Jun 26, 2017) No need to find remaining work. They asked to find only how much time to complete the 110 pages. So total pages done by both (40/3) * 110.

 Rahul said: (Sep 17, 2017) Please tell me the calculation of (110 x 3/40).

 Piyush said: (Oct 28, 2017) @Amansamana. Ravi-192 Kumar-200 And applying lcm is not right approach as work is not same in both the cases. so solution given is best for this type of question. @Rahul 40/3 pages together in 1 hour. 1 page together in 3/40 hour. 110 pages in (110 x 3/40).

 Pooja said: (Jan 10, 2018) 1/4*60 => 15 min.

 Annapurna Kashyap said: (Feb 7, 2018) Elan's 1 hour work = 40/5 =8. Elan's 6 hour work = 8*6 = 48. Pages written by Ronald and Elan in 6 hours = 48+32 = 80. ( M^1*H^1/W^1=M^2*H^2/W^2). 2*6/80=2*x/110 (as x is the no of hours taken by both to write 110 pages). = x=33/4= 8hours and 15 min.

 Rahul said: (Nov 23, 2018) 8.25 hr means 8 * 60 min + .25 * 60 min. .25 *60 min = 15 min. That is why the answer is 8 hr 15 min. or 8.25* 60 = 495, 80*60=480, 495-480=15 min.

 Navya Sri said: (Nov 10, 2019) Can any one explain me that why you multipled with 3/40 with 110. But we got 40/3 for 1 hour.

 Neeraj said: (Apr 3, 2020) Time taken by Ravi for typing 32 pages=6hours. Time taken by Kumar for typing 40 pages=5hours. Therefore, time taken for Ravi for typing 1 page=6/32. Similarly, time taken by Kumar for typing 1 page=5/40. So, time taken when both worked together for typing 1page= (6/32) + (5/40). Time taken when both worked together for typing 110 pags=110* ( (6/32) + (5/40)). Is this method valid? Anyone suggest me.

 Himanshu said: (Jun 10, 2020) Ravi typed 32 pages in 6 hrs that mean in one hour he typed 6 pages. Kumar typed 40 pages in 5hrs that mean in one hour he typed 8 pages. If they both work together they can type 8+6=14 pages per hour. Now they have to type 110 page and they can type 14 page per hour. 110/14 = 7.85 =7 hrs and 85 min =8hrs and 15 min.

 Pema said: (Oct 30, 2020) @Himanshu, Your method is very simple and clean, thanks. But 32/6 gives you approximately 5.33. Following your steps, the answer is option D. Which is 8hours:25mins. Please check it.

 Ladshika Mohan said: (Nov 10, 2020) 3*110/40 = 8.25 then how come 8.15?