In the past, Ben has been able to hit a baseball at the batting cage 20% of the time. He decides to head back to the batting cage. What is the probability that his first hit will be on the eighth pitch? Round your answer to the nearest ten-thousandth.

Respuesta :

The probability is 0.336.

To solve this, we need Binomial Probability equation for Repeated Trials.

P = nCr (p)^r (q)^(n-r)
where P = probability (unknown)
          n = number of trials (8)
          r = number of successes (1)
          p = probability of success (.20)
          q = probability of failure (0.80)

P = 8C1 (.20)^1 (.80)^7
   = 0.336