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:
202 comments Page 12 of 21.
Mishi said:
10 years ago
I can't understand how 10 days come 1/10? If anyone can explain it?
Purushottam Kumar said:
10 years ago
(6m+8b)*10 = (26m+48b)*2.
=> (6m+8b)*5 = 26m+48b.
=> 30m+40b = 26m+48b.
=> 4m = 8b.
=> m = 2b.
=> m/b = 2x/x (let).
Now, total work = (6m+8b)*10.
=> (6*2x+8*x)*10.
=> 200x.
Now, (15m+20b)*n = 200X (where n is required number of days).
=> (15*2x+20*x)*n = 200x.
=> (50x)*n = 200x.
=> n = 4 days.
=> (6m+8b)*5 = 26m+48b.
=> 30m+40b = 26m+48b.
=> 4m = 8b.
=> m = 2b.
=> m/b = 2x/x (let).
Now, total work = (6m+8b)*10.
=> (6*2x+8*x)*10.
=> 200x.
Now, (15m+20b)*n = 200X (where n is required number of days).
=> (15*2x+20*x)*n = 200x.
=> (50x)*n = 200x.
=> n = 4 days.
Divya said:
10 years ago
Please solve these equation i.e: 2x+3y = 1/10 and 3x+2y = 1/8.
Bikash Choudhury said:
1 decade ago
It is simple method.
6m-----+8w-------- = 10.
6*10=60----8*10---- = 80....equation 1.
26m------+48w-------- = 2.
26*2=52------48*2=96....equation 2.
Equation 1- Equation 2.
60-52 = 8 and 96-80 = 16.
8:16 = 1:2.
12w+8w = 10.
=> 20w = 10.
=> 1w = 20*10.
We have to find 15m+20w = ?
=> 30w+20w = 50w = 200.
=> w = 200/50 = 4 days.
6m-----+8w-------- = 10.
6*10=60----8*10---- = 80....equation 1.
26m------+48w-------- = 2.
26*2=52------48*2=96....equation 2.
Equation 1- Equation 2.
60-52 = 8 and 96-80 = 16.
8:16 = 1:2.
12w+8w = 10.
=> 20w = 10.
=> 1w = 20*10.
We have to find 15m+20w = ?
=> 30w+20w = 50w = 200.
=> w = 200/50 = 4 days.
S.Sabarish said:
1 decade ago
Hello @Siddarth,
Your answers are extremely convincing. Please do give short cuts for other problems too.
Your answers are extremely convincing. Please do give short cuts for other problems too.
Bhargavi namballa said:
1 decade ago
I didn't understand. Could you please explain once again?
Qasim said:
1 decade ago
Hello to all I am confuse in x value.
6x+8y=1/10 ----- (i).
26x+48y=1/2 ------ (ii).
Multiply 1st equation into 6, then we get:
36x+48y=1/10*6.
26x+48y=1/2.
Change the sign of 2nd equation.
36x+48y=3/5.
-26x-48y=-1/2.
The result is:
10x=3/5-1/2.
10x=1/10.
Then,
x= 1/10/10= 10/1*10= 100/1=100.
Therefore x= 100.
Is it right please any one tell me.
And also tell me why in upward first solution there is x=1/100.
6x+8y=1/10 ----- (i).
26x+48y=1/2 ------ (ii).
Multiply 1st equation into 6, then we get:
36x+48y=1/10*6.
26x+48y=1/2.
Change the sign of 2nd equation.
36x+48y=3/5.
-26x-48y=-1/2.
The result is:
10x=3/5-1/2.
10x=1/10.
Then,
x= 1/10/10= 10/1*10= 100/1=100.
Therefore x= 100.
Is it right please any one tell me.
And also tell me why in upward first solution there is x=1/100.
Michelle said:
1 decade ago
I'm still confuse about how we got 1/100 and 1/200. I'm trying to figure out this problem from formula perspective (TIME X RATE = WORK).
However, it seems like everyone is just free styling with there methods to this question, I need structure.
However, it seems like everyone is just free styling with there methods to this question, I need structure.
Anee said:
1 decade ago
2x+3y=10, 3x+2y=8, 2x+1y=?
Esan said:
1 decade ago
What is wrong if I try to solve it like this:
6x+8y=10.
26x+48y=2.
Arrive at the value of x&y, then find 15x+20y to get the answer?
Can anyone explain? Thanks.
6x+8y=10.
26x+48y=2.
Arrive at the value of x&y, then find 15x+20y to get the answer?
Can anyone explain? Thanks.
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