Homework7solutions

Homework7solutions - Steven Weber Dept. of ECE Drexel...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Steven Weber Dept. of ECE Drexel University ENGR 361: Statistical Analysis of Engineering Systems (Spring, 2008) Homework 7 Solutions (Monday, May 12) Question 1: Exercise 37, § 5.3, p212. A particular brand of dishwasher soap is sold in three sizes: 25 oz, 40 oz, and 65 oz. 20% of all purchasers select a 25-oz box, 50% select a 40-oz box, and the remaining 30% choose a 65-oz box. Let X 1 and X 2 denote the package sizes selected by two independently selected purchasers. a. Determine the sampling distribution of ¯ X , calculate E [ ¯ X ] , and compare to μ . x 1 x 2 p ( x 1 , x 2 ) ¯ x 25 25 0 . 04 25 . 0 25 40 0 . 10 32 . 5 25 65 0 . 06 45 . 0 40 25 0 . 10 32 . 5 40 40 0 . 25 40 . 0 40 65 0 . 15 52 . 5 65 25 0 . 06 45 . 0 65 40 0 . 15 52 . 5 65 65 0 . 09 65 . 0 ¯ x 25 . 0 32 . 5 40 . 0 45 . 0 52 . 5 65 . 0 p x ) 0 . 04 0 . 20 0 . 25 0 . 12 0 . 30 0 . 09 (1) and E [ ¯ X ] = 25 . 0 × 0 . 04 + 32 . 5 × 0 . 20 + 40 . 0 × 0 . 25 + 45 . 0 × 0 . 12 + 52 . 5 × 0 . 30 + 65 . 0 × 0 . 09 = 44 . 5 μ = 25 . 0 × 0 . 20 + 40 × 0 . 50 + 65 × 0 . 30 = 44 . 5 (2) b. Determine the sampling distribution of the sample variance S 2 , calculate E [ S 2 ] , and compare to σ 2 . x
Background image of page 1

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

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 06/24/2008 for the course ENGR 361 taught by Professor Eisenstein during the Spring '04 term at Drexel.

Page1 / 3

Homework7solutions - Steven Weber Dept. of ECE Drexel...

This preview shows document pages 1 - 2. Sign up to view the full document.

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