In 1955, Life Magazine reported that a 25-year-old mother of three worked (on average) an 80 hour week. Recently, many groups have been studying whether or not the women's movement has, in fact,...

In 1955,Life Magazine reported that a 25-year-old mother of three worked (on average) an 80 hour week. Recently, many groups have been studying whether or not the women's movement has, in fact, resulted in an increase in the average work week for women (combining employment and at-home work). Suppose a study was done to determine if the average work week has increased. 67 women were surveyed with the following results. The sample average was 83; the sample standard deviation was 10. Does it appear that the average work week has increased for women at the 5% level?


Note: If you are using a Student'st-distribution for the problem, you may assume that the underlying population is normally distributed. (In general, you must first prove that assumption, though.)