A farmer counts his cows and chickens. If he counts 20 heads and 64 feet, how many chickens does he have?

1 Answer
Nov 12, 2016

The farmer has #8# chickens.

Explanation:

We let the number of cows be #x# and the number of chickens be #y#.

We know that each creature must only have one head, hence we derive our first equation #-> x + y = 20#.

We also know that a cow has 4 feet while a chicken only has #2#. So our second equation is #4x + 2y = 64#.

Let's start by simplifying the second equation.

#2(2x + y) = 64 -> 2x+ y = 32#

#{1} y = 20 - x ->2x + 20 - x = 32#

#x = 12#

#x+ y = 20#

#12 + y= 20#

#y = 8#

So, there are #12# cows and #8# chickens.

Hopefully this helps!