In Probability, expected return is the measure of the average expected probability of various rates in a given set. The process could be repeated an infinite number of times. The term is also referred to as expected gain or probability rate of return. Here is an online probability calculator which helps you to calculate the percentage of expected rates of return.
P1 = 30 R1= 10
P2 = 45 R2 = 20
P3 = 25 R3 = 30
Expected Gain = (30 x 10) + (45 x 20) + (25 x 30) = 300 + 900 + 750 =1950
Expressing in %, probability rate of return (expected return) is 1950 / 100 = 19.5 %