The total cost of buying 3 cameras from Amazon for both Maddox and Theo was 3*$20=$<<3*20=60>>60
Maddox sold his cameras at $28 each, for a total of $28*3=$<<28*3=84>>84
Maddox made a profit of $84-$60=$<<84-60=24>>24 from the sale of his cameras.
Theo sold his cameras on eBay for $23*3=$<<23*3=69>>69
Theo made a profit of $69-$60=$<<69-60=9>>9
Maddox made $24-$9=$15 more profit than Theo from the sale of his cameras.
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