Aptitude - Time and Work - Discussion
Discussion Forum : Time and Work - General Questions (Q.No. 19)
19.
A, B and C can complete a piece of work in 24, 6 and 12 days respectively. Working together, they will complete the same work in:
Answer: Option
Explanation:
| Formula: If A can do a piece of work in n days, then A's 1 day's work = | 1 | . |
| n |
| (A + B + C)'s 1 day's work = |  |
1 | + | 1 | + | 1 |  |
= | 7 | . |
| 24 | 6 | 12 | 24 |
| Formula: If A's 1 day's work = | 1 | , | then A can finish the work in n days. |
| n |
| So, all the three together will complete the job in | |
24 | days |
= | 3 | 3 | days. | 7 | 7 |
Discussion:
24 comments Page 2 of 3.
Seshapriya said:
1 decade ago
24*6 + 6*12 + 12*24 / 24*6*12 =144+72+288 / 1728
=504/1728
i.e
1728/504 days
24/7=
= 3 3/7 days option c..........
=504/1728
i.e
1728/504 days
24/7=
= 3 3/7 days option c..........
Swetha said:
1 decade ago
Given:
A can do a work in 24 days
B can do a work in 6 days
C can do a work in 12 days
Take LCM for 24,6 & 12 i.e 24
total work = 24
A's per day capacity = 24/24 = 1
B's per day capacity = 24/6 = 4
C's per day capacity = 24/12 = 2
If all working together,
their per day capacity = 1+4+2 = 7
all together will complete the work in 24/7 = 3 3/7 days
A can do a work in 24 days
B can do a work in 6 days
C can do a work in 12 days
Take LCM for 24,6 & 12 i.e 24
total work = 24
A's per day capacity = 24/24 = 1
B's per day capacity = 24/6 = 4
C's per day capacity = 24/12 = 2
If all working together,
their per day capacity = 1+4+2 = 7
all together will complete the work in 24/7 = 3 3/7 days
Sarthak said:
1 decade ago
Why did you ppl Reciprocal 7/24 ?
Aditya said:
1 decade ago
Thank you dharma you helped me alot.
Dharma said:
1 decade ago
A's work be x,
B's work be y
C's work be z
Total work done by A,B,C(A+B+C)=(X*Y*Z)/(XY+YZ+XZ)
Solution is:
x=12
y=6
z=24
A+B+C=(12*6*24)/(12*6+6*24+24*12)
= 24/7
= 3 and (3/7)
B's work be y
C's work be z
Total work done by A,B,C(A+B+C)=(X*Y*Z)/(XY+YZ+XZ)
Solution is:
x=12
y=6
z=24
A+B+C=(12*6*24)/(12*6+6*24+24*12)
= 24/7
= 3 and (3/7)
Mohit said:
2 decades ago
Hey look at the question first he is asking days for completion of work so If A's 1 day's work = 1/n then A can finish the work in n days its reciprocal of it.
Maheswari said:
2 decades ago
i can't get... how 1/n
Muthukumar said:
2 decades ago
I am not understand how to you got 7/24.
Sanjukta Nayak said:
2 decades ago
Me confused,please help
Simon said:
2 decades ago
I didn't get how you got 7/24.
Post your comments here:
Quick links
Quantitative Aptitude
Verbal (English)
Reasoning
Programming
Interview
Placement Papers