Question

In a garrison, there was food for 1000 soldiers for one month. After 10 days, 1000 more soldiers joined the garrison. How long would the soldiers be able to carry on with the remaining food?  

(a) 25 days (b) 20 days (c) 15 days (d) 10 days

Answer 1

(d) Let the remaining food last for x days.

1000 soldiers had provisions for (30 – 10) = 20 days

(1000 + 1000) men had provisions for x days.

More men, less days (indirect proportion)

∴  2000 : 1000   : :   20 : x