Aptitude - Time and Work - Discussion
Discussion Forum : Time and Work - General Questions (Q.No. 1)
1.
A can do a work in 15 days and B in 20 days. If they work on it together for 4 days, then the fraction of the work that is left is :
Answer: Option
Explanation:
| A's 1 day's work = | 1 | ; |
| 15 |
| B's 1 day's work = | 1 | ; |
| 20 |
| (A + B)'s 1 day's work = |  |
1 | + | 1 |  |
= | 7 | . |
| 15 | 20 | 60 |
| (A + B)'s 4 day's work = | |
7 | x 4 | |
= | 7 | . |
| 60 | 15 |
| Therefore, Remaining work = | |
1 - | 7 | |
= | 8 | . |
| 15 | 15 |
Discussion:
355 comments Page 17 of 36.
Abhinesh said:
8 years ago
Let,
Do in this way;
Use formula= xy/x+y.
X is 15 and Y 30 if you cross multiply you get an answer.
Do in this way;
Use formula= xy/x+y.
X is 15 and Y 30 if you cross multiply you get an answer.
Vikrant said:
10 years ago
Simple that how get 7/60. 15 + 20/15 * 20 = 35 / 300.
So, 7 * 5 = 35 & 60 * 5 = 300. Thats it!
So, 7 * 5 = 35 & 60 * 5 = 300. Thats it!
Innareddy chilakala said:
10 years ago
(15 * 20)/15 + 20 = 60/7.
Work done in 4 days (7/60) * 4 = 7/15,
Remaining work is 1 - 7/15 = 8/15.
Work done in 4 days (7/60) * 4 = 7/15,
Remaining work is 1 - 7/15 = 8/15.
Akanksha said:
2 decades ago
(1/50+1/20) = (20+15)/300 //This get by cross multiplication.
= 35/300
= 7/60.
How did 300 came?
= 35/300
= 7/60.
How did 300 came?
Latha said:
1 decade ago
Work done=>4*(1/15)+4*(1/20) = 7/15.
Remaining work = 1-7/15.
= 8/15.
Option D.
Remaining work = 1-7/15.
= 8/15.
Option D.
Surya said:
6 years ago
(1/15+1/20).
Fractions of 15 and 20 are written as;
3*5 and 2'2 *5. = 60,
and 35 go for 7,
= 7/60.
Fractions of 15 and 20 are written as;
3*5 and 2'2 *5. = 60,
and 35 go for 7,
= 7/60.
Chandradeepa said:
7 years ago
By considering LCM 60 in that case why should we need to do remaining work divided by total work.
Jaiprakash said:
9 months ago
A > 15 both LCM 60.
B > 20.
(A+B ) * 4 = 60.
7 * 4 = 28.
60 - 28/60.
32/60 = 8/15.
B > 20.
(A+B ) * 4 = 60.
7 * 4 = 28.
60 - 28/60.
32/60 = 8/15.
(16)
Sugan said:
2 years ago
1 (total work) - 7/15 (together completed work in 4 days).
Lcm = 15 then (15/15 -7/15) = 8/15.
Lcm = 15 then (15/15 -7/15) = 8/15.
(8)
Vikki ls said:
1 decade ago
Hi sir,
How would you calculate the 7/16*4 for to knowing the 4/15=60 ?
Please tell me sir.
How would you calculate the 7/16*4 for to knowing the 4/15=60 ?
Please tell me sir.
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