Philip has 50/100 * 20 = <<50/100*20=10>>10 more ducks than cows.
Which means he has 20 + 10 = <<20+10=30>>30 ducks.
So Philip's cows and ducks sum up to 20 + 30 = <<20+30=50>>50 animals.
If there are 50 cows and ducks, that means Philip has 1/5 * 50 = <<50*1/5=10>>10 pigs.
In total Philip has 50 + 10 = <<50+10=60>>60 animals on his farm.
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