Chicken pecking rice problem

Let the chicken peck rice as x, then the hen peck rice as 2x and the rooster peck rice as 4x.

x+2x+4x= 100 1

7x= 100 1

x= 143

Chicken pecked rice 143 grains.

Hen pecked rice 2x=286 grains.

The cock pecked rice 4x=572 grains.