Question 474080
k = n + n+2 + n+4
k = 3n + 6
n = k/3 - 2
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n + n+2 = 2n + 2
= 2(k/3 - 2) + 2
= 2k/3 - 4 + 2
= 2k/3 - 2
or (2k - 6)/3