Aptitude - Time and Work - Discussion
Discussion Forum : Time and Work - General Questions (Q.No. 6)
6.
If 6 men and 8 boys can do a piece of work in 10 days while 26 men and 48 boys can do the same in 2 days, the time taken by 15 men and 20 boys in doing the same type of work will be:
Answer: Option
Explanation:
Let 1 man's 1 day's work = x and 1 boy's 1 day's work = y.
| Then, 6x + 8y = | 1 | and 26x + 48y = | 1 | . |
| 10 | 2 |
| Solving these two equations, we get : x = | 1 | and y = | 1 | . |
| 100 | 200 |
| (15 men + 20 boy)'s 1 day's work = |  |
15 | + | 20 |  |
= | 1 | . |
| 100 | 200 | 4 |
15 men and 20 boys can do the work in 4 days.
Discussion:
204 comments Page 16 of 21.
V nirmal kumar said:
1 decade ago
6 men and 8 boys are in the ratio 6:8=3:4.
15 men and 20 boys are also in the same ratio 15:20=3:4.
Common factor for the first combination is 2 and common factor for the second combination is 5.
So if it take 10 days for the first combination then.
5 : 2.
10 : ?
= 4.
As you can see the common factors are in the ratio of the number of days needed to finish the work.
15 men and 20 boys are also in the same ratio 15:20=3:4.
Common factor for the first combination is 2 and common factor for the second combination is 5.
So if it take 10 days for the first combination then.
5 : 2.
10 : ?
= 4.
As you can see the common factors are in the ratio of the number of days needed to finish the work.
Pradeep Oram said:
1 decade ago
@Sidharth.
There is also mentioned 2nd eq. i.e 26x+48y = 1/2.
And it doesn't relate to 3rd eq.
It may your procedure is quite wrong?
There is also mentioned 2nd eq. i.e 26x+48y = 1/2.
And it doesn't relate to 3rd eq.
It may your procedure is quite wrong?
Suresh C B said:
1 decade ago
I have More smarter way to solve this.
6 Man and 8 Boys takes 10 days.
15 Man And 20 boys are 2.5 time more than 6 man and 8 boys so, this man and boys group takes 2.5 times less TIME 10/2.5 = 4.
6 Man and 8 Boys takes 10 days.
15 Man And 20 boys are 2.5 time more than 6 man and 8 boys so, this man and boys group takes 2.5 times less TIME 10/2.5 = 4.
Varun bansal said:
1 decade ago
I can suggest a new method:
6 men + 8 boys = 10 days
=> 60 men + 80 boys = 1 day
=> 30 men + 40 boys = 2 days - eq.1.
But given that
26 men + 48 boys = 2 days - eq.2.
From one and two eqns.
4 men = 8 boys.
i.e. 1 man = 2 boys.
From eqn 1. 100 boys = 2 days.
50 boys = 4 days.
30 boys + 20 boys = 4 days.
15 men + 20 boys = 4 days.
6 men + 8 boys = 10 days
=> 60 men + 80 boys = 1 day
=> 30 men + 40 boys = 2 days - eq.1.
But given that
26 men + 48 boys = 2 days - eq.2.
From one and two eqns.
4 men = 8 boys.
i.e. 1 man = 2 boys.
From eqn 1. 100 boys = 2 days.
50 boys = 4 days.
30 boys + 20 boys = 4 days.
15 men + 20 boys = 4 days.
Hari said:
1 decade ago
We can do this in single step.
6 men and 8 boys can do work in 8 days.
So 6m+8b=1/10
So we have to find 15m+20b=?
6m+8b=1/10.
Divide each term by 2 in both side we get
3m+4b=1/20.
And multiply each term with 5
15m+20b=5*120.
15m+20b=1/4.
So answer is 4 days simple.
6 men and 8 boys can do work in 8 days.
So 6m+8b=1/10
So we have to find 15m+20b=?
6m+8b=1/10.
Divide each term by 2 in both side we get
3m+4b=1/20.
And multiply each term with 5
15m+20b=5*120.
15m+20b=1/4.
So answer is 4 days simple.
Sinto Antony said:
1 decade ago
This can be solved with one equation
6 men & 8 boys can do the work in 10 days
Multiply this with 2.5 gives 15 men & 20 boys
Divide the number of days by same factor 2.5 = 10 days / 2.5
i.e. 4 days :)
6 men & 8 boys can do the work in 10 days
Multiply this with 2.5 gives 15 men & 20 boys
Divide the number of days by same factor 2.5 = 10 days / 2.5
i.e. 4 days :)
Shubham said:
1 decade ago
Thanks shiddhu.
SSUMEDH said:
1 decade ago
(6Men+8Boy).10=(26Men+48Boy).2
Solve the above equation
1Men=2Boy
15Men+20Boy=25Men
Solve the above equation
1Men=2Boy
15Men+20Boy=25Men
Kumudha said:
1 decade ago
Thank you Siddharth, But is this same way to solve same kind of sum.
Prajesh said:
1 decade ago
2x+3y=1/10 ----- (1).
3x+2y=1/8 ------ (2).
We want to find: 2x+1y=?---- (3).
Any one can solve this.
3x+2y=1/8 ------ (2).
We want to find: 2x+1y=?---- (3).
Any one can solve this.
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