His plantation is 500*500=<<500*500=250000>>250,000 square feet
That means he gets 250,000*50=<<250000*50=12500000>>12,500,000 grams of peanuts
So he makes 12,500,000*5/20=<<12500000*5/20=3125000>>3,125,000 grams of peanut butter
So he has 3,125,000/1000=<<3125000/1000=3125>>3125 kg of peanut butter
That means it sells for 3125*10=$<<3125*10=31250>>31,250
#### 31250