sol.hw6.stat3011 - Homework 6 Solutions Yicheng Kang 6.30 x...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Homework 6 Solutions Yicheng Kang October 29, 2010 6.30 z = x - μ σ = - . 75 which corresponds to a cumulative probability of 0 . 2266. z = x - μ σ = . 5 which corresponds to a cumulative probability of 0 . 6915. 0 . 6915 - 0 . 2266 = 0 . 4649(rounds to 0 . 46), the approximate proportion of students who get a C. 6.61 z = (258 - 281 . 9) / 11 . 4 = - 2 . 10; according to Table A, 0 . 0179 fall below this z-score; thus, propor- tion 0 . 018 of babies would be classified as premature. 7.20 a) The mean would be 8 . 20. Standard error = σ/ n = 3 / 100 = 0 . 30. b) z = (8 , 95 - 8 . 20) / 0 . 3 = 2 . 5.Table A tells us that 0 . 994 is the proportion below this z-score. Thus, the probability that the restaurant makes a profit that day is 0 . 994. 7.24 a)The center of the population distribution is the mean of the population of 60. The spread is the standard deviation of the population,16. 1
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
b)The center of the data distribution 58 . 3 The spread is the standard deviation of 15 . 0. It is probably skewed to the left. c) The center of the sampling distribution mean is 60. The spread, or standard error, is
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

This document was uploaded on 04/28/2011.

Page1 / 3

sol.hw6.stat3011 - Homework 6 Solutions Yicheng Kang 6.30 x...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online