Statıstıcs Iı Deneme Sınavı Sorusu #1055174
A random sample of 410 from two class in a high school is chosen. 250 of the students is selected from class (A) and their particular subject's mean test score is 70 with a standard deviation of 5. The rest of the students is selected from class (B) and their mean test score is 65 with a standard deviation of 4. At the 1% significance level, can we conclude that class (A) mean test score is better than the class (B)?
|
20 |
|
25 |
|
30 |
|
35 |
|
40 |
The independent random sample sizes are nA = 250 students and nB = 160 students. Also, the class (A) mean test score is xA = 70 and standard deviation sA = 5, and the class (B) mean test score is xB = 65 and standard deviation sB= 4. Then, the test statistic can be obtained as follows: xA - xB = 70 - 65 = 5, sA2 = 25, sB2 = 16. Therefore [(25/250)+(16/160)] = 1/5. The test statistic z=5/(1/5)=25
The answer is B.
Yorumlar
- 0 Yorum