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:
4 days
5 days
6 days
7 days
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:
198 comments Page 3 of 20.

Meera said:   1 decade ago
Hi Sangeetha its very easy to solve this equations.

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
x=1/100

Then apply x value into 1st equation
6x+8y=1/10
6*1/10+8y=1/10
8y=4/100
y=1/200

Thats it.
(3)

Bikash Choudhury said:   10 years 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.

Krishna said:   1 decade ago
(6M & 8B)10Days > (60M & 80B)..(1).

(26M & 48B)2Days > (52M & 96B)...(2).

Subtract 1 And 2 We get 8M & 16B.

Time Taken To Complete the work = Ratio= 2(M):1(B).

Now, (15M & 20B) = ? ...(03).

Put the ratio of 2:1 in (03),
We get 50.

Also put ratio in (1),
we get 200.

So total work/M + B = 200/50 = 4days.

YASEEN said:   2 years ago
Here in 1st case, there are 6 men and 8 boys = [6+8=14] and their work done is 10.
So, 10*14 = 140[total work done by men and boys,

Similarly,
In 2nd case 26+48 = 74,
74*2 = 140.

The Total work done by 15 men and 20 boys is 15+20=35 and let their work done be x.
Now 35 * x
.
From the above work done take anyone.
140 = 35*x,
x = 4.
(69)

Srujan said:   9 years ago
If you practice well this would be a short cut.
(6Men + 8Boy).10 = (26Men + 48Boy).2.

=> (6Men + 8Boy).5 = (26Men + 48Boy).1.

30m => 48B
26m =>40B
------------------
4m = 8B

1Men = 2Boy
15Men + 20Boy = 25Men
6men + 4men = (1men = 2Boy)
10men --> 10days
25men---?

So,
10*10 = 25*D
D = 4days.
25men = 15men + 20boy = 4days.

Arun said:   2 years ago
From given data,

6M+8B ---> 10days.
26M+48B ---> 2days.
15M+20B ---> t days.

By using Product approach
WF1*T1=WF2*T2.

(6M+8B)*10=(26M+48B)*2,
4M=8B,
M/B=2/1,
M=2;B=1.

Now substitute We get;
20 --->10 days.
100 --->2 days.
50 ---> t days.
100*2=50*t(Product approach)
t=4 i.e.,4 days.
(40)

Purushottam Kumar said:   9 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.

PRAVEEN K PILLAI said:   1 decade ago
6 men X 10= 60
8 men X10 = 80 i.e 60m = 80b.

So 1 men = 4/3 boys, So 6 men = 6 x 4/3-8 boys.
So 8+8 = 16 boys completes work in 10 days.

Now the case of 15 men and 20 boys.
15 men = 15 x 4/3 = 20 boys, So 15 men and 20 boys = 40 boys.

If 16 boys can do a work in 10 days then 40 boys will be able to do in 16 x10/4 = 4 days.

Sai naresh said:   7 years ago
Hi, I am Sai Naresh.

Another simple way of solving the 6th question.

(M*D*H)/W=(M*D*H)/W.
By using this formula we can do many ques.
(M) Men, it may be boy or girl just add up.
D days.
H hours.
W work.

If, data is not mentioned just remove what u don't need.
14*10=74*2=35*X.
BY EQUATING 14*10=35*X.
X = 140/35 = 4days.

Vijay said:   8 years ago
Guys. No need to get in to the equation. If 6 man and 8 boys can do a work in 10 days. So obviously 12 men's and 16 boys can complete this in 5 days. (Since the count of the mens and boys is 15 and 20 respectively. So the number of the day will be reduce more. So the only option is 4 which is below 5) so the answer is 4.


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