According to Net Market Share, Microsoft's Internet Explorer browser has 53.4% of the global market. A random sample of 70 users was selected. What is the probability that 32 or more from this sample used Internet Explorer as their browser?
A)0.9608
B)0.9015
C)0.7266
D)0.8050

Question

Quizplus · Accepted Answer

The probability can be calculated using the normal approximation to the binomial distribution. With p = 0.534, n = 70, the mean is np = 37.38 and the standard deviation is sqrt(np(1-p)) ≈ 4.18. Using the z-score formula, the probability of 32 or more users is approximately 0.9015.

According to Net Market Share, Microsoft's Internet Explorer Browser Has