Answer: 792
Explanation:
From what I got it should be 792 because it is asking for doubles, triples, and home runs all together at the same amount that he got on his first year.
It says after 12 years
Doubles 47 times 12 years = 564
Triples 4 times 12 years = 48
and
Home runs 15 times 12 years = 180
564 + 48 = 612
612 + 180 = 792