Let x = 2nd #
x + 1 = 4th #
2x - 1 = 1st #
10 - x = 3rd #
14 - (10 - x) = 4 + x = 5th #
x + x + 1 + 2x - 1 + 10 - x + 4 + x = 30
4x + 14 = 30
4x = 16
x = 4
7 - first number
4 - second number
6 - third number
5 - fourth number
8 - fifth number
Order of the numbers: 74658