Since they must total 30, and be equal, divide 30 in half. 30 divided by 2 will give you the answer.
-17
25
There are 30 such numbers.
30
30 is not a ratio. In a ratio, two numbers are always specified, for example, 30:1. If that's what you mean, you can simply multiply both numbers - in this case, 30 and 1 - by any real number (both by the same real number), to get an equivalent ratio.
They are: 30*30 = 900
6 and -5
The two consecutive numbers which when added equal 59 are 29 and 30.
31
-117
-30
42
43
-17
-958
-17
47