Question 587671
Let sheep be x
and chicken be y

Each has only 1 head
so x+y =60..................(1)

Sheep has 4 legs and chicken 2
4x+2y=200....................(2)

Multiply (1) by -2 and add the equation to (2)
-2x-2y=-120
4x+2y=200

Therefore 2x= 80
/2
x= 40

sheep 40 numbers balance 20 are chickens

CHECK

40*4 +20*2= 200