Question 332690
Hello, 
Let's have p represent pigs and c show chickens. Now we can set up 2 equations as:
p + c = 220
4p + 2c=700
Now multiply the first equation by -2 to get:
-2p-2c=-440
Add this to the second equation to get:
2p=260
Divide by 2 to get:
p=130
There we go, there are 130 pigs. 
Make sense?
RJ
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