Aptitude - Time and Work - Discussion
Discussion Forum : Time and Work - General Questions (Q.No. 29)
29.
A and B can do a job together in 7 days. A is 1
times as efficient as B. The same job can be done by A alone in :
times as efficient as B. The same job can be done by A alone in :Answer: Option
Explanation:
| (A's 1 day's work) : (B's 1 day's work) = | 7 | : 1 = 7 : 4. |
| 4 |
Let A's and B's 1 day's work be 7x and 4x respectively.
| Then, 7x + 4x = | 1 |  11x = |
1 | x = |
1 | . |
| 7 | 7 | 77 |
 A's 1 day's work = |
 |
1 | x 7 |  |
= | 1 | . |
| 77 | 11 |
Discussion:
53 comments Page 4 of 6.
Juhi said:
9 years ago
If 4/7 of a piece of work is completed in 7/4 days, in how many days can rest of the work be completed?
M.vignesh said:
1 decade ago
A=7/4
B=1
A:B=7/4:1
So A:b=7:4
Total Working Days=7*4=28
a=28/7=4
b=28/4=7
a=a+b
a=4+7=11
A alone=11
B=1
A:B=7/4:1
So A:b=7:4
Total Working Days=7*4=28
a=28/7=4
b=28/4=7
a=a+b
a=4+7=11
A alone=11
Divya said:
1 decade ago
Because a is 7/4 times efficient than b => a= 7/4b
a:b= 7/4b:b (b's get cancelled.)
=> 7/4:1
a:b= 7/4b:b (b's get cancelled.)
=> 7/4:1
Kriti said:
9 years ago
Guys I am not getting the concept of equation 1 and 2 please any one explain me in detail, please.
Padma said:
8 years ago
Why have they taken efficiency as such without converting it to number of days?
Yashwanth said:
8 years ago
What will be the answer for same problem with A is twice the efficiency of B?
Iovd said:
1 decade ago
@Raj.
They given 1*3/4 in example after solving it we get 7/4(4*1+3).
They given 1*3/4 in example after solving it we get 7/4(4*1+3).
Adithya vinay kumar said:
9 years ago
How come efficiency is directly proportional to the no of days worked?
Heena said:
1 decade ago
@nidhi
if A=(7/4)B
then Eq2 should be
7/4(B)+B=1/7
if A=(7/4)B
then Eq2 should be
7/4(B)+B=1/7
Siri said:
9 years ago
How you are getting 7/4? Anybody explain it please.
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