# Additional problems_3_stud on statistical distributions -...

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

Additional problems_ 3_stud on statistical distributions.doc // See handouts #8 and 9 Apr 7’10 Sampling Distribution of the Sample Means //Use the program Three_Distributions.doc , sheet 3 In addition to HW #6 the following problems may be considered. 5.3.4 , pg. 139, textbook . Wright et al. used the 1999-2000 National Health and Nutrition Examination Survey (NHANES) to estimate dietary intake of 10 key nutrients. One of those nutrients was calcium (mg). They found in all adults 60 years and older a mean daily calcium intake of 721 mg with a standard deviation of 454 mg. Using these values for the mean and standard deviation for the US population find the probability that a random sample of size 50 will have a mean: a ) Greater than 800 mg _ __ Solution. µ x_mean = µ = 721 G58, σ x_mean = σ/√n = 454/√50 = 64.2 G59 _ _ P(X > 800) = 1 – f(X ≤ 800) =

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

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: 0.109249 I60 b ) Less than 700 mg P(X ≤ 700) = c ) Between 700 and 850 mg P(700 ≤ X ≤ 850) = P(X ≤ 850)- f(P(X ≤ 700) =0.97775-0.371795=0.605955 P(700 ≤ X ≤850)= f(X≤850)-f(X≤700) 5.3.6 , pg. 140, textbook . Given a normally distributed population with a mean of 100 and a standard deviation of 20 , find the following probabilities based on a sample of size 16 . _ ( a ) P(X ≥ 100) _ _ Solution. P(X ≥ µ) = 1 – f(X ≤ µ) = 1/2- general result _ __ µ x_mean = µ = 100 G58, σ x_mean = σ/√n = 20/√16 = 5 G59 _ X = 100 G57 _ _ P(X ≥ 100) = 1 – f(X ≤ 100) = 0.5 I60 _ ( b ) P(X ≤ 110) Solution: X= 110 G57 1 P(X≤110)= f(X≤110)=0.97725 I59 _ (c) P(96 ≤ X ≤ 108) I59 I59 P(96 ≤ X ≤ 108) =f (X≤108)-f(X≤96)= 0.945201-0.211855=0.733346 2...
View Full Document

## This note was uploaded on 11/24/2011 for the course MATH 3000 taught by Professor Kzaer during the Spring '05 term at St. Johns College MD.

### Page1 / 2

Additional problems_3_stud on statistical distributions -...

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

View Full Document
Ask a homework question - tutors are online