Better random

Random.cs

float GreaterRandom(float[] lttRate)
{
    float total = 0;

    foreach (float elem in lttRate)
    {
        total += elem;
    }

    float randomPoint = Random.value * total;

    for (int i = 0; i < lttRate.Length; i++)
    {
        if (randomPoint < lttRate[i])
        {
            return i;
        }
        else
        {
            randomPoint -= lttRate[i];
        }
    }
    return lttRate.Length - 1;
}