According to a Wakefield Research survey of adult women, 50% of the women said that they had tried five or more diets in their lifetime (USA TODAY, June 21, 2011). Suppose that this result is true for the current population of adult women. A random sample of 13 adult women is selected. Use the binomial probabilities table (Table I of Appendix C) or technology to find the probability that the number of women in this sample of 13 who had tried five or more diets in their lifetime is
a. at most 7
b. 5 to 8
c. at least 7