Answer:
The answer is: The largest number is 15.
Explanation:
Let n = the number
n + (n + 1) + (n + 2) + (n + 3) = (n + 4) + (n + 5) + (n + 6)
4n + 6 = 3n + 15
n = 9
Proof:
9 + 10 + 11 + 12 = 19 + 23 = 42
13 + 14 + 15 = 27 + 15 = 42
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