1) The mean monthly mortgage paid by all home owners in a city is $1340 with a standard deviation of $120. Using Chebyshev's theorem, find the interval, [L, U] that contains monthly mortgage payments of at least 80% of all homeowners.

2) suppose the times taken to learn the basics of the word processor by all students have a bell-shaped distribution with a mean of 200 minutes and a standard deviation of 20 minutes. Using the empirical rule, find the percentage of students who learn the basics of this word processor in 140 to 260 minutes.

3)

Chapter 03, Section 3.3, Additional Question 011 * Incorrect. The following table gives the grouped data on the weights of all 100 babies born at a hospital in 2009. Weight (pounds) Number of Babies 3 to less than 5 5 to less than 7 20 7 to less than 9 30 9 to less than I1 15 I I to less than 13 33 Calculate the mean, variance, and standard deviation. Round your answers to two decimal places