In the study of 75 undergraduate students and 50 graduate students, the undergraduates had a mean reported number of hours sleeping of 6.18667 with a standard deviation of 1.04872 hrs. The graduate students had a mean of 6.42 hours with a standard deviation of 1.03194 hours. Use StatCrunch to run the t-test. What is the test statistic? What is the p-value associated with that test statistic? Give the most appropriate conlcusion in context The is evidence to support the claim that undergraduates sleep less than graduate students. Undergraudates sleep the same amount of time as graduate students. There is not evidence to reject the claim that underegraduates sleep the same amount as graduate students. We accept the claim that undergraduates sleep less than graduate students. Check Answer

Suppose the scores of students on an exam are normally distributed with a mean of 253 and a standard deviation of 80. According to the empirical rule, what percentage of students scored between 13 and 493 on the exam?

Suppose that IQ scores have a bell-shaped distribution with a mean of 103 and a standard deviation of 14. Using the empirical rule, what percentage of IQ scores are at least 145?

The shelf life of a battery produced by one major company is known to be Normally distributed, with a mean life of 3.5 years and a standard deviation of 0.75 years. What is the upper quartile of battery shelf life? Use the fact that the middle 50% of the data falls within 0.67 standard deviations from the mean.

The heights of 10 year old American children are normally distributed with a mean height of 4 feet and 5 inches (or 53 inches) and a standard deviation of 4.5 inches.In order to be allowed to go on a particular kids ride at the amusement park, children must be at least 44.9 inches tall and no more than 59.75 inches tall.What percent of 10 year old American children cannot go on the ride?

The combined SAT scores for the students at a local high school are normally distributed with a mean of 1469 and a standard deviation of 296. The local college includes a minimum score of 1824 in its admission requirements. What percentage of students from this school earn scores that satisfy the admission requirement?