Question

Name: Date: Hypothesis Testing One-Sample Variance ing all the time. It seems that nearly every Homework Problems be cost of milk seems to be escalating all the time. It se store has raised their prices consis claims that the standard deviati always been, .275. In looking at the deviation was at .301. At the .05 deviation is still what the FDA says it is. hair prices consistently during the past few months. The EA e standard deviation of milk prices is much the same as it ha In looking at the prices of milk in 25 local stores, the stand iac at 301. At the .05 alpha level, test the claim that the standard 2. The New York Knicks have been al Vark Knicks have been a last-place team for a long time. The numbe frames they have won has been very consistent over the past 20 years with a standard deviation of only 3.65. At the .01 alpha level, test the claim that the team has been far less consistent than the owners claim of 2.83 games 2. During the last month of the season, New York Yankees pitchers had a difficult time getting beyond the fifth inning. Their performances had been remarkably poor and consistently so. The standard deviation for the average number of in nings pitched had been 0.94. Test the claim that the standard deviation was far more for the Yankees than the major league average of 0.667. 4. While gasoline prices have fluctuated all over the map in the last few months, dealers claim that they have maintained a very steady standard deviation for those prices. The major dealer believes that the standard deviation should be 3.44. In checking 51 price changes for the local BLD station, the value for "S" was 17. Test the claim that the standard deviation has remained consistent

Answer 1

Question 1.

Given:

$1588013170337_blob.png$ = 0.05, n = 25, S = 0.301, $1588013170347_blob.png$ = 0.275

Hypothesis:

Ho: $1588013170365_blob.png$ = 0.275

Ha: $1588013170382_blob.png$ $\neq$ 0.275 (Two tailed test)

Test statistic:

$\chi ^{2} = \frac{(n-1)S^{2}}{\sigma ^2}= \frac{(25-1)0.301^{2}}{0.275 ^2} = 28.75$

Degree of freedom = n-1 = 25-1 = 24

P-value = 0.2296            ..............Using chisquare table

Conclusion:

P-value > $\alpha$ , i.e 0.2296 > 0.05, That is Fail to Reject Ho at 5% level of significance.

Therefore, support to Claim that the standard deviation is still what the FDA says it.