Please solve these questions and why we choose the answers. Thanks! 14. The leve
ID: 3354433 • Letter: P
Question
Please solve these questions and why we choose the answers. Thanks! 14. The level of calcium in the blood of healthy young adults follows a Normal distribution with a mean of = 10 milligrams per deciliter and a standard deviation of -04 milligrams. A clinic measures the blood calcium of 100 healthy pregnant young women at their first visit for prenatal care. The mean of these 100 measurements is x-9.8. Is this evidence that the mean calcium level in the population of healthy pregnant young women is less than 10? To answer this, test the hypotheses H: -10 versus H: 1.5. Determine whether each of the following statements is true or false. A) The probability that Ho is true is 0.05 B) The data were statistically significant at -0.05. C) At the 5% significance level, 11, should be rejected. D) Even if nicotine content in cigarettes of this brand were not quite Normally distributed, the test would still be valid. 16. A college student is doing some research on the cost of one-bedroom apartments in town. He has randomly selected 25 apartments for which the price was published. The average price for these apartments is $652. He will assume that price follows roughly a Normal distribution. Based on prices from previous years, a real estate agent gives him the information that is approximately S55. A 95% confidence interval for is found to be 652 ± 21.56 = (S630.44$673.56). Determine which of the following statements is TRUE A) A test of the hypotheses Ho: -650 versus H: 650 would be rejected at the B) C) D) 0.05 level. A test of the hypotheses Ho: = 650 versus H: > 650 would be rejected at the 0.05 level. A test of the hypotheses H0: -675 versus H: # 675 would be rejected at the 0.05 level. All of the above
Explanation / Answer
Please post 1 question per post. Here' answer to 1st question. Write back in case of doubts:
We have been given params of the normal distribution. Lets list them down below:
Pop. Mean = 10
Pop. dev = 0.4
n = 100
xbar = 9.8
Ho: Mu = 10
Ha: Mu < 10
We calculate the Z statistic using the following formula:
So, Z = (Xbar-Pop.Mean)/(Pop.dev/sqrt(n)) = (9.8-10)/(.4/sqrt(100)) = -5.
-1.96 is the lower tail cutoff of Z for alpha = .05.
Since this less than -1.96 it falls under rejection region. Ho is rejected
Hence, A is CORRECT