Aptitude - Time and Work - Discussion
Discussion Forum : Time and Work - General Questions (Q.No. 8)
8.
A can do a certain work in the same time in which B and C together can do it. If A and B together could do it in 10 days and C alone in 50 days, then B alone could do it in:
Answer: Option
Explanation:
| (A + B)'s 1 day's work = | 1 |
| 10 |
| C's 1 day's work = | 1 |
| 50 |
| (A + B + C)'s 1 day's work = |  |
1 | + | 1 |  |
= | 6 | = | 3 | . .... (i) |
| 10 | 50 | 50 | 25 |
A's 1 day's work = (B + C)'s 1 day's work .... (ii)
| From (i) and (ii), we get: 2 x (A's 1 day's work) = | 3 |
| 25 |
 A's 1 day's work = |
3 | . |
| 50 |
 B's 1 day's work |
|
1 | - | 3 | |
= | 2 | = | 1 | . |
| 10 | 50 | 50 | 25 |
So, B alone could do the work in 25 days.
Discussion:
148 comments Page 6 of 15.
Nagu said:
1 decade ago
Hi Guys, sorry for the late and here is the explanation about you doubt.
In my previous explanation I mentioned
(a+b+c)'s one day work = 3/25
and a+b+c = 2a here b+c=a means a's one day work = b+c's one day work
then a's one day work+(b+c)'s one day work = 3/25
so a+a = 3/25
2a = 3/25
so here 2* a's one days work = 3/25
So I think u can under stand now
keep practicing.....
In my previous explanation I mentioned
(a+b+c)'s one day work = 3/25
and a+b+c = 2a here b+c=a means a's one day work = b+c's one day work
then a's one day work+(b+c)'s one day work = 3/25
so a+a = 3/25
2a = 3/25
so here 2* a's one days work = 3/25
So I think u can under stand now
keep practicing.....
DHARMENDRA said:
1 decade ago
A=B+C-----------------(1)
A+B=1/10--------------(2)
C=1/50----------------(3)
(1)+(2)
(B+C)+B=1/10-----------(4)
(3)+(4)
B+(1/50)+B=1/10
2B=(1/10)-(1/50)
B=1/25
SO B COMPLETE THE TASK IN 25 DAYS
A+B=1/10--------------(2)
C=1/50----------------(3)
(1)+(2)
(B+C)+B=1/10-----------(4)
(3)+(4)
B+(1/50)+B=1/10
2B=(1/10)-(1/50)
B=1/25
SO B COMPLETE THE TASK IN 25 DAYS
Suresh said:
1 decade ago
From given statement
A+B+C = 6/50 ( A+B = 1/10 and C = 1/50)
Substitute A= B+C in above equation to get A= 3/50
3/50+B+1/50 = 6/50
B = 1/25
25 days
A+B+C = 6/50 ( A+B = 1/10 and C = 1/50)
Substitute A= B+C in above equation to get A= 3/50
3/50+B+1/50 = 6/50
B = 1/25
25 days
Mohanapriyadarshini said:
1 decade ago
@awoke
How come 2 b's ?
A + B = 1/10 but A = B + C, then
A + B = B + B + C = 1/10 and C = 1/50
a value is a+b ,what about b+c, why you are adding b+b+c ?
How come 2 b's ?
A + B = 1/10 but A = B + C, then
A + B = B + B + C = 1/10 and C = 1/50
a value is a+b ,what about b+c, why you are adding b+b+c ?
Nikhil said:
1 decade ago
Mr.Awoke your method is awesome and moreover its applicable to all such type of probs...thanks!
Pavan@9966606261 said:
1 decade ago
A=B+C;
A+B=1/10;
A-B=1/50;
2A=1/10+1/50=6/50;
A=3/50;
A-B=1/50;
B=3/50-1/50;
B=1/25;
B ALONE CAN DO IN "25" DAYS
A+B=1/10;
A-B=1/50;
2A=1/10+1/50=6/50;
A=3/50;
A-B=1/50;
B=3/50-1/50;
B=1/25;
B ALONE CAN DO IN "25" DAYS
Sowmya said:
1 decade ago
@awoke.
Your method is awesome.
Your method is awesome.
Rakesh sonowal said:
1 decade ago
A=B+C (1)
A+B 1 Day work=1/10 (2)
Cs 1 Day work=1/50 (3)
putin eq (1) n (3) in eq (2)
2B +1/50=1/10
2B=1/10-1/50
2B=(5-1)/50
2B=4/50
B=4/50 =1/25
So Bs 1 day work =1/25.
So B alone could do d work in 25 days.
A+B 1 Day work=1/10 (2)
Cs 1 Day work=1/50 (3)
putin eq (1) n (3) in eq (2)
2B +1/50=1/10
2B=1/10-1/50
2B=(5-1)/50
2B=4/50
B=4/50 =1/25
So Bs 1 day work =1/25.
So B alone could do d work in 25 days.
GAURAV said:
1 decade ago
TIME FOR CERTAIN WORK....
A=B+C .....................................i
FOR
A+B=10 DAY.......SO(A+B)_1DAY WORK=1/10
.>A=1/10-B.......................ii
C=50 DAY.........1 DAY C WORK=1/50......................iii
SO ...FOR B=A-C.........................FROM i
B=1/10-B-1/50
2B=1/10-1/50
B=1/25
.........SO B REQUIRE 25 DAYS
A=B+C .....................................i
FOR
A+B=10 DAY.......SO(A+B)_1DAY WORK=1/10
.>A=1/10-B.......................ii
C=50 DAY.........1 DAY C WORK=1/50......................iii
SO ...FOR B=A-C.........................FROM i
B=1/10-B-1/50
2B=1/10-1/50
B=1/25
.........SO B REQUIRE 25 DAYS
Dinesh said:
1 decade ago
@AWOKE.
I liked your method. Thank you.
I liked your method. Thank you.
Post your comments here:
Quick links
Quantitative Aptitude
Verbal (English)
Reasoning
Programming
Interview
Placement Papers