Each student in a class of 40 was randomly assigned one line of a random number table. Each student then counted the odd-numbered digits in a 30-digit line. (Remember that 0, 2, 4, 6, and 8 are even.)
a. On average, in the list of 30 digits, how many odd-numbered digits would each student find?
b. If each student found a 90% confidence interval for the percentage of odd-numbered digits in the entire random number table, how many intervals (out of 40) would you expect not to capture the population percentage of 50%?