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?
7 hours 30 minutes
8 hours
8 hours 15 minutes
8 hours 25 minutes
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

Therefore 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 4 of 6.

KUMAR ABHISHEK said:   9 years ago
How the answer is option C?

The correct answer is 8 hours 25 minutes.

KAUSHAL said:   9 years ago
Yes its answer should be D.

Pritam Kumar said:   10 years ago
Every step is correct till the last. Only calculation mistake is there. It's answer should be option D: 8 hours 25 minutes.

Khoshali said:   10 years ago
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.
(1)

Ranji said:   10 years ago
D is the option C is incorrect it comes as 8.25 hrs and not 8.15 hrs.

Gnanamayil said:   1 decade ago
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.

Vivek said:   1 decade ago
How will you get 8 1/4 when you multiply 110*3/40?

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.
(1)

Anil said:   1 decade ago
1 hr = 60 minutes.
0.25 hr = x.
Cross multiplication.
60*0.25 = 15.

Divya said:   1 decade ago
@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.


Post your comments here:

Your comments will be displayed after verification.