hi

canu tell me how it will be 300

initially farmer has x no. of chikens and that last up to d days

Then food he want is x*d

now he want to selll 75 chickens so x-75 no of chickens and food last up to 20 days more means d+20. still our initial food is the same x*d.

now he want to buy chickens so x+100 of chickens and food last up to 15 days less means d-15. still our initial food is the same x*d.

now two equations we get

(x-75)*(d+20) xd

(x+100)*(d-15) xd by solving we get x 300 and d 60