A garrison of 3300 men had provisions for 32 days, when given at the rate of 850 grams per head.....

Question

A garrison of 3300 men had provisions for 32 days, when given at the rate of 850 grams per head. At the end of 7 days, reinforcement arrives and it was for that the provisions will last 17 days more, when given at the rate of 825 grams per head, what is the strength of the reinforcement?

Answer 1

the 3300 men x 32 days x 850 grams/day-man = 89,760,000 grams

3300 men x 7 days x 850 grams/day-man = 19,635,000 (used)

subtract 70,125,000 (left)

then (3300+a) x 10 days x 825 grams/day-man = 70,125,000

a = reinforcements = 5200 men