Aptitude - Time and Work - Discussion
Discussion Forum : Time and Work - General Questions (Q.No. 17)
17.
A is 30% more efficient than B. How much time will they, working together, take to complete a job which A alone could have done in 23 days?
Answer: Option
Explanation:
Ratio of times taken by A and B = 100 : 130 = 10 : 13.
Suppose B takes x days to do the work.
Then, 10 : 13 :: 23 : x  x = |
 |
23 x 13 |  |
x = |
299 | . |
| 10 | 10 |
| A's 1 day's work = | 1 | ; |
| 23 |
| B's 1 day's work = | 10 | . |
| 299 |
| (A + B)'s 1 day's work = | |
1 | + | 10 | |
= | 23 | = | 1 | . |
| 23 | 299 | 299 | 13 |
Therefore, A and B together can complete the work in 13 days.
Discussion:
119 comments Page 6 of 12.
Prachi said:
4 years ago
A is 30% more efficient than B.
So, Assume 100: 130.
then ratio is 10:13.
Now cross multiple the value 10:13.
23:x..........(23 day)
13*23/10 = 299/10.
A=1/23,B = 299/10.
i.e 1/23 + 10/299 = 23/299 = 1/13.
So, Assume 100: 130.
then ratio is 10:13.
Now cross multiple the value 10:13.
23:x..........(23 day)
13*23/10 = 299/10.
A=1/23,B = 299/10.
i.e 1/23 + 10/299 = 23/299 = 1/13.
(8)
Amrith said:
1 decade ago
@shakthi.
Then A's efficiency(A/C to question) = x+x*(30/100) = 13x/10....(2).
They are telling that a is 30% more efficient than b right. So it will be A=30/100 + x right....why x is multiplies with 30/100.
Then A's efficiency(A/C to question) = x+x*(30/100) = 13x/10....(2).
They are telling that a is 30% more efficient than b right. So it will be A=30/100 + x right....why x is multiplies with 30/100.
Nilu said:
1 decade ago
Given that A is 30% efficient than B then
A=130% and b=100%
so 130%=23 days
then 100%=23*100/130=230/13
so B' 1 day work=13/230 and A' 1 day work=1/23
(A+B) one day work=(1/23+13/230)=10
so the answer is D
A=130% and b=100%
so 130%=23 days
then 100%=23*100/130=230/13
so B' 1 day work=13/230 and A' 1 day work=1/23
(A+B) one day work=(1/23+13/230)=10
so the answer is D
Tom cruz said:
8 years ago
A's efficiency = 100/23 = 4.35;
since A is 30% more efficient than B:
A = 30%B + B or A = 1.3B or B = A/1.3;
then B = 4.35/1.3 = 3.35;
then, working together;
4.35 + 3.35 = 7.7;
100/7.7 = 12.98 or 13 days.
since A is 30% more efficient than B:
A = 30%B + B or A = 1.3B or B = A/1.3;
then B = 4.35/1.3 = 3.35;
then, working together;
4.35 + 3.35 = 7.7;
100/7.7 = 12.98 or 13 days.
Dawood Sheriff said:
1 decade ago
Actually A is more efficient than B as per the question,
Then A could be 130% of B.
B = 10/13*23=230/13.
A = 1/23 ,for a day.
B = 230/13, for a day.
Therefore (A + B)T = 1.
(13/230 + 1/23)T = 1.
T = 10.
Then A could be 130% of B.
B = 10/13*23=230/13.
A = 1/23 ,for a day.
B = 230/13, for a day.
Therefore (A + B)T = 1.
(13/230 + 1/23)T = 1.
T = 10.
Sreepadh Reddy said:
1 decade ago
I got the answer as 10 days.
a:b = 130:100 as a is 30% more efficient than b.
So a:b = 130:100.
From which we get,
130:100::23:x.
a's work is = 1/23;
b's work is = 13/230.
a+b = 1/23+13/230 = 10.
a:b = 130:100 as a is 30% more efficient than b.
So a:b = 130:100.
From which we get,
130:100::23:x.
a's work is = 1/23;
b's work is = 13/230.
a+b = 1/23+13/230 = 10.
Sujan Roy said:
9 years ago
130% of works = 1/23,
1% of works = 1/130 * 23,
100% of work = 100 * 1/130 * 23,
= 10/299,
Then A and B together = 1/23 + 10/299,
= 13 + 10/299,
= 23/299,
= 1/13 then 13 day is the answer.
1% of works = 1/130 * 23,
100% of work = 100 * 1/130 * 23,
= 10/299,
Then A and B together = 1/23 + 10/299,
= 13 + 10/299,
= 23/299,
= 1/13 then 13 day is the answer.
Vishnuvardhan said:
8 years ago
As per the given data;
A = 130%B.
then
A = 130/100 B.
1/23 = 130/100 B. (as we know A=1/23)
B = 10/(13*23),
B = 10/299.
A and B together work is;
1/23 + 10/299,
23/299,
= 1/13.
Hence 13 days.
A = 130%B.
then
A = 130/100 B.
1/23 = 130/100 B. (as we know A=1/23)
B = 10/(13*23),
B = 10/299.
A and B together work is;
1/23 + 10/299,
23/299,
= 1/13.
Hence 13 days.
Revathy said:
5 years ago
Efficiency of A=B+ (30/100) B (Efficiency of A is 30% more than B) =1/23.
A=B (1+30/100) =1/23.
B 13/10=1/23.
B=10/299.
If together A+B=1/23+10/299 =1/13.
Therefore the time taken is 13.
A=B (1+30/100) =1/23.
B 13/10=1/23.
B=10/299.
If together A+B=1/23+10/299 =1/13.
Therefore the time taken is 13.
(3)
Shada Akhtar said:
9 years ago
A = (130/100) *B (because A is 30% more efficient than B).
A =13B/10.
A =1/23 (Given).
1/23 = 13B/10.
B = 0/299.
A + B = 1/23 +10/299.
= 23/299 = 1/13.
Hence, both will take 13 days.
A =13B/10.
A =1/23 (Given).
1/23 = 13B/10.
B = 0/299.
A + B = 1/23 +10/299.
= 23/299 = 1/13.
Hence, both will take 13 days.
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