Some math help, please

I have 3 values, which are:

560
500
-156

560 happens 21.3% of the time
500 happens 19.8% of the time
-156 happens 58.9% of the time

With a total range of 716 what would I work out what the average value is, using those percentages?

The weighted average of the 3 numbers would be calculated like this

weighted average = 560 * (0.213) + 500 * (0.198) + -156 * (0.589)

= 126.396

so the weighted average is 126.396.