Question

A military camp has provisions for 630 men to last for 25 days.How many men must be transferred to another camp so that the food lasts for 30 days?

Answer 1

Given:

Number of men in camp = 630

Total number of days for which the food will last = 25

It is given that total food amount is same and food has to last for 30 days.

For this to happen, some men have to be shifted to other camp.

Let x be total number of men shifted to other camp.

Now, number of men in the camp = (630-x)

And, Total number of days for which the food will last = 30

$\Rightarrow 630 \times 25=(630-x)\times 30\\\Rightarrow (630-x) = \dfrac{630 \times 25}{30}\\\Rightarrow (630-x) = 21 \times 25\\\Rightarrow (630-x) = 525\\\Rightarrow x = 630 -525\\\Rightarrow x =105$

i.e. 105 men should be moved to other camp so that the same food can last for 30 days.