Question

5. You have just detemined a 95% 2-sided confidence interval on the difference between the two population means, -H2, where is the population mean yield of chemical process 1 and is the population mean yield of chemical process 2. Your result is L = -1.02 and U 2.32. In a 2-sided test of hypothesis on the equality of these two means, He , what would have been your conclusion? Enter the letter of the correct answer on the answer sheet A. Reject Ho. There is evidence that the population means are not equal B. Fail to reject Ho. There is not evidence that the population means are different C. Cannot draw a conclusion based on the information given 6. In a study of the relationship of the shape of a tablet to the time it takes to dissolve in water, five oval-shaped ibuprofen tablets and four round-shaped ibuprofen tablets were dissoved in water The time, in seconds, each took to dissolve was: Round: 268, 260, 273, 278 Oval: 243, 269, 242, 255, 253 Perfom a test of hypothesis to detemine if the mean time to dissolve in water is different between the two shapes Use P(Type I error) 0.05. Which is the best way to express the conclusion of your test? Enter the letter of the best answer on the answer sheet A. Reject Ho. There is evidence that the mean time to dissove is different between the tablet shapes. B. Fail to reject Ho. There is not evicdence that the mean time to dissolve is different between the tablet shapes. C. Accept H There is evidence that the mean time to dissolve is different between the tablet shapes. D. Reject H There is not evidence that the mean time to dissolve is different between the tablet shapes E. None of the above.

Answer 1

Solution-5:

The confidence interval contains zero

-1.02<0<2.32

So Fail to reject null hypothesis,

Accept null hypothesis.

MARK OPTION B

Solution-6:

Perform t test for difference in means as

File Home Insert Page Layout Formulas Data a Show Queries Connections From Table Properties et External New Refresh Data Query Le Recent Sources All Edit Links Get & Transform Connections Review View Help Tell me what you want to ALZA Y Clear E Flash Reapply Remo 2 Sort Filter Text to Advanced Columns Data Sort & Filter fox OVAL D C E Data Analysis ? X 1 x | A B OVAL ROUND 243 268 269 260 242 273 ок | Cancel Analysis Tools Histogram Moving Average Random Number Generation Rank and Percentile Regression Sampling t-Test: Paired Two Sample for Means t-Test: Two-Sample Assuming Equal Variances t-Test: Two-Sample Assuming Unequal Variances z-Test: Two Sample for Means Help 255 253

t-Test: Two-Sample Assuming Unequal Variances
	OVAL	ROUND
Mean	252.4	269.75
Variance	119.8	58.9166667
Observations	5	4
Hypothesized Mean Difference	0
df	7
t Stat	-2.78936
P(T<=t) one-tail	0.013467
t Critical one-tail	1.894579
P(T<=t) two-tail	0.026933
t Critical two-tail	2.364624

t=-2.789

p=0.0269

p<0.05

Reject Ho

There is suffIcient evidence to support the claim that means are different

MARK OPTION A