Aptitude - Chain Rule - Discussion

Good explation vikas. Thanks.

There are 150 men and they have food for 45 days.

So available food = 150*45 = 6750.

After 10 days 25 men left.

So food consumed for 10 days 150*10 = 1500.

Now avail food = 6750-1500 = 5250.

Avail food = 5250 and there are 125 men.

So this food avail for = 5250/125 = 42 days.

HI,

I am always confused to solve time and work questions, so please help me to solve this problem in easy way.

(150*45-150*10)/125.

After solving this we get answer is negative. That is not exist.

Thank you @Vikas.

In the first way mentioned example. Why they are considering 150 men food for 35 days. I mean, for only 10 days 150 men will have food. So after that only, remaining 125 men will have food for 35 days na. Clarify my doubt.

It means that for 35 days 150 men have enough food.
So 25 leave.

Now the question is how many days will the remaining food be enough for 125 men.

How can you say that total food available is 150*45?

It can be a multiple of 150*45 also.

Let the total amount of food available be x (for 150 men, for 45 days).

Therefore food available for 150 men per day = x/45.

Food available per man per day = (x/45)/150.

Can someone tell me what is the problem in this approach?

Solution step by step:

45 days ---> 150 men ---> 1 food.

1 day ---> 150*45 men ----> 1 food.....equation(1).

10 days ---> (150*45)/10 men ---> 1 food.

10 days ---> 1 man ---> 10/(150*45) food.

10 days ---> 150 men ---> 10/45 food.

Remaining food 1 - 10/45 = 35/45 food.

From equation (1),

1 food ---> 150*45 men ----> 1 day.

1 food ---> 1 man ----> 150*45 days.

35/45 food ---> 1 man ----> 35*150 days.

Remaining men after 10 days = 150-25 = 125 men.

35/45 food ---> 125 men ----> 35*150/125 days = 35*6/5 = 42 days.

(150*45) = (10*150)+(125*y).

So y = 42.

In the start, total food (150*45).

1-10 days used food (10*150).

After 10 days remaining food (125*y).

So (150*45) = (150*10) + (125*y).

y = 42.