Enrico was able to sell the 30-kilogram rooster for 30 x 0.50 = $<<30*0.50=15>>15.
And he was able to sell the 40-kilogram rooster for 40 x 0.50= $<<40*0.50=20>>20.
Therefore, he was able to earn $20 + $15 = $<<20+15=35>>35.
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