Answer: A, C, E
Solve for all the inequalitites.
n + 5 < 9
n < 9 - 5
n < 4
∴ n = 3 is a part of the solution set.
13n < 1
n < 1/13
∴ This definitely doesn't include n = 3.
3n + 1 > 7
3n > 6
n > 2
∴ n = 3 is part of the solution because n is larger than 2.
3n > 9.5
n > 9.5 ÷ 3
n > 3.16666666
∴ n = 3 is not part of the solution set.
n - 2 < 5
n < 5 + 2
n < 7
∴ n = 3 is a part of the solution set.