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:
351 comments Page 4 of 36.
Sowmiya said:
2 years ago
How remaing work =1? Please explain to me.
(20)
Radhika said:
3 years ago
@All.
As 1 is the whole work, so when we subtract 7/15 from 1.
Then,
LCM of 1 and 15 will be 15 ( in 1 the denominator will be 1 ).
So, 15-7/15 is 8/15.
As 1 is the whole work, so when we subtract 7/15 from 1.
Then,
LCM of 1 and 15 will be 15 ( in 1 the denominator will be 1 ).
So, 15-7/15 is 8/15.
(18)
SFG said:
9 months ago
Thanks for explaining the answer @Anjali thakur.
(18)
RichardAnthony said:
3 years ago
Just take LCM of 15 and 20 you will get total work of 60.
(17)
Ankita said:
4 years ago
@Jyoti.
It's 1 -7/15 as it is asking how much work is left. Which means 1 is the total amount of work, and 7/15 is the amount of work completed.
So, to get the remaining work we hv to subtract the work done by the whole work. Which is
1-7/15.
= 15/15 - 7/15.
= 15-7/15.
= 8/15.
Hope it helps.
It's 1 -7/15 as it is asking how much work is left. Which means 1 is the total amount of work, and 7/15 is the amount of work completed.
So, to get the remaining work we hv to subtract the work done by the whole work. Which is
1-7/15.
= 15/15 - 7/15.
= 15-7/15.
= 8/15.
Hope it helps.
(15)
Hari said:
2 years ago
@Vishnu.
Can you explain the process in detail please?
Can you explain the process in detail please?
(15)
Ashim said:
2 years ago
How 7/60 came? Anyone, please explain to me.
(14)
GAGAN said:
2 months ago
15, 20 LCM 60.
A = 4
B = 3 TOTAL WORK 60
A + B WORK
then 4 + 3 = 7,
TOTAL 28
60 - 28 = 32.
32/60.
= 8/15.
A = 4
B = 3 TOTAL WORK 60
A + B WORK
then 4 + 3 = 7,
TOTAL 28
60 - 28 = 32.
32/60.
= 8/15.
(14)
VisHnu RaM said:
4 years ago
Thank you for giving the clear explanation @Swetha.
And 60 will come, No of days LCM
15 days to 15 * 4 = 60.
20 days to 20 * 3 = 60.
So, the LCM is 60.
And 60 will come, No of days LCM
15 days to 15 * 4 = 60.
20 days to 20 * 3 = 60.
So, the LCM is 60.
(13)
Bhawana said:
5 months ago
Please explain me about the remaining work.
(12)
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