Aptitude - Time and Work - Discussion
Discussion Forum : Time and Work - General Questions (Q.No. 26)
26.
A and B can do a work in 8 days, B and C can do the same work in 12 days. A, B and C together can finish it in 6 days. A and C together will do it in :
Answer: Option
Explanation:
| (A + B + C)'s 1 day's work = | 1 | ; |
| 6 |
| (A + B)'s 1 day's work = | 1 | ; |
| 8 |
| (B + C)'s 1 day's work = | 1 | . |
| 12 |
 (A + C)'s 1 day's work |
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So, A and C together will do the work in 8 days.
Discussion:
54 comments Page 2 of 6.
Ivan said:
4 years ago
Thanks for explaining @Parveen Verma.
(1)
Nandhu said:
9 years ago
a+b=8,b+c=12,a+b+c=6.
LCM(8,12,6)=24.
a+b=24/8=3,b+c=24/12=2,a+b+c=24/6=4,
(a+b+c)-(a+b)=1,(a+b+c)-(b+c)=2,
c=1 a=2.
a+c=3,24/3=8.
ans:8.
LCM(8,12,6)=24.
a+b=24/8=3,b+c=24/12=2,a+b+c=24/6=4,
(a+b+c)-(a+b)=1,(a+b+c)-(b+c)=2,
c=1 a=2.
a+c=3,24/3=8.
ans:8.
(1)
Santosh said:
9 years ago
A+B ....8 DAY- 3unit. L.C.M-24 UNIT
B+C......12 DAY - 2 unit.
A+B+C......6 DAY -(24/6)...4 unit .
Then,
A+B+C=4. A+B=3....(3+C=4 =C=1)
C=1.
B+C=2 UNIT .....C=1.
B=1.
A+B=3.
B=1.
A=2 .
A and c's work.
A+c=2+1=3 unit per day,
Total work =24 unit,
A+c=24/3=8 day.
B+C......12 DAY - 2 unit.
A+B+C......6 DAY -(24/6)...4 unit .
Then,
A+B+C=4. A+B=3....(3+C=4 =C=1)
C=1.
B+C=2 UNIT .....C=1.
B=1.
A+B=3.
B=1.
A=2 .
A and c's work.
A+c=2+1=3 unit per day,
Total work =24 unit,
A+c=24/3=8 day.
Vishal sinha said:
8 years ago
It can be done in a much simpler way.
(A+B)'s 1-day work = 1/8.
(B+C)'s 1-day work = 1/12.
(A+B)+(B+C)'s 1 day work= 1/8+1/12.
B+(A+B+C)=5/24,
B=5/24-1/6,
B=1/24.
So, A+B+C=1/6,
Putting the value of B.
(A+C)'s 1 day work = 1/6 - 1/24 = 1/8.
Time taken = 8 days.
(A+B)'s 1-day work = 1/8.
(B+C)'s 1-day work = 1/12.
(A+B)+(B+C)'s 1 day work= 1/8+1/12.
B+(A+B+C)=5/24,
B=5/24-1/6,
B=1/24.
So, A+B+C=1/6,
Putting the value of B.
(A+C)'s 1 day work = 1/6 - 1/24 = 1/8.
Time taken = 8 days.
Deep said:
9 years ago
Thanks @Parveen.
Vikas said:
9 years ago
Thanks for the explanation.
Dimple said:
9 years ago
Thank you for all your explanations.
Gregory wachiye said:
1 decade ago
This is awesome. I have gained a lot with the help of this explanations.
Raghav said:
1 decade ago
Excellent guys! Keep it up.
Chary said:
9 years ago
good explanation, thanks all.
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