In an army camp, there were provisions for 550 men for 28 days. But, 700 men attended the camp. How long did the provisions last?

Given, in an army camp, there were provisions for 550 men for 28 days, but, 700 men attended the camp.

Now, by using a unitary method:

Number of days that provisions will be for 550 men = 28 days

→ Number of days that provisions will be for 1 man = $28 \times 550$

= 15400 days(fewer men mean more days for provision)

→ Number of days that provisions will be for 700 men = $\frac{15400}{700}$

= 22 days 

Hence, the provision will last for 22 days only if 700 men attend the camp.