Aptitude - Time and Work - Discussion
Discussion Forum : 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?
Answer: Option
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 |
Discussion:
53 comments Page 1 of 6.
Mohammed Ashraf said:
1 decade ago
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.
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.
(1)
NEERAJ said:
5 years ago
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.
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.
(2)
Sunny said:
1 decade ago
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.
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.
Himanshu said:
5 years ago
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.
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.
(18)
JIGSAW said:
9 months ago
Ravi takes 6 hours to type 32 pages =>7.5 hours to type 40 pages.
Kumar takes 5 hours to type 40 pages.
if they work together & assignment of 110 pages.
WKT after 7.5, 40 pages of Ravi + 40 of Kumar + 20 pages of Kumar = 100 pages - 7 hours 30 mins.
110 pages.
We get 8 hours and 15 min.
Kumar takes 5 hours to type 40 pages.
if they work together & assignment of 110 pages.
WKT after 7.5, 40 pages of Ravi + 40 of Kumar + 20 pages of Kumar = 100 pages - 7 hours 30 mins.
110 pages.
We get 8 hours and 15 min.
Kishore said:
1 decade ago
@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.
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.
Arunkumar said:
9 years ago
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.
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.
Tara said:
9 years ago
@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.
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.
(1)
Harsh said:
9 years ago
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.
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.
(1)
Piyush said:
8 years ago
@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).
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).
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