According to the National Education Association, the country's largest teachers union, the proportion of men in teaching is at its lowest level in 40 years. Only 21 percent of teachers in U.S. public schools are men. In early grades, the gender ratio is even more imbalanced just 9 percent of elementary school teachers are men. Suppose we randomly select 120 teachers who work in U.S. public schools What is the (approximate) probability that less than 20 of these teachers are men?
Question 2
A random sample of 30 airline flights during a storm had an average delay of 40 minutes. The standard deviation was 5 minutes. Calculate a 98 confidence interval for the average delay for all flights during a storm.
a. (37.8, 42.2)
b. (38.2, 41.8)
c. (27.7, 52.3)
d. None of the above
Chimpanzees in the Gombe National Park, Tanzania groom each other by holding an overhead branch with
The USGS National Shaking Hazard Map