binomial distribution

Question

What is the expected value for the binomial distribution below?

successes: 0,1,2,3,4,5

probability: 1/3125, 4/625, 32/625, 128/625, 256/625, 1024/3125

Answer 1

Since the binomial distribution is discrete, the expected value is computed by ∑p(x)*x where x is the outcome and p(x) is the probability of that outcome. So in this case, the expected value is 0*(1/3125)+1*(4/625)+2*(32/625)+3*(128/625)+4*(256/625)+5*(1024/3125).