SOLUTION: A farmer looks out into the barn yard and sees the pigs and chickens. He says to his daughter, I count 40 heads and 100 feet . How many pig s and how many chicken are there?

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Question 743921: A farmer looks out into the barn yard and sees the pigs and chickens. He says to his daughter, I count 40 heads and 100 feet . How many pig s and how many chicken are there?
Answer by tommyt3rd(5050) About Me  (Show Source):
You can put this solution on YOUR website!
Let's use
P-#pigs
C-#chickens
I count 40 heads: every animal has a head so...
P%2BC=40

...and 100 feet...
Pigs have 4 feet so 4P is the number of Pig's feet he sees and by the same thinking 2C is how many Chicken's feet. So...
4P%2B2C=100
To make our work easier we'll divide every term by 2...
2P%2BC=50

We have 2-equations and 2-unknowns:
P%2BC=40
2P%2BC=50
From the top equation we can say
C=40-P
Next
2P%2BC=50
becomes...
2P%2B%2840-P%29=50
From which we can quickly deduce that there are 10 pigs. And since there are 40 animals there must be 30 chickens.
:)