Difference of two Means. A national testing agency decided to do an experiment to see about the value of using a computer in a mathematics class. One group of students (Group A) used a computer in their class, while another group (Group B) did not. The main variable of interest was a test score, and we want to see if the mean test score for Group A is Larger than Group B. Use alpha = .05 for your test.
The sample statistics are given below for each group.
Group A | Group B | |
Mean Score | 320 | 302 |
Standard Deviation | 29.5 | 32.1 |
N | 20 | 20 |
We can assume the two variances are equal. What is the pooled Standard Error for this problem? Just give an answer. Use 4 decimal places and use the proper rules of rounding.
So,
Answer is:
9.7485
Difference of two Means. A national testing agency decided to do an experiment to see about the value of using a compute...
Question 27 3 pts Difference of two Means. A national testing agency decided to do an experiment to see about the value of using a computer in a mathematics class. One group of students (Group A) used a computer in their class, while another group (Group B) did not. The main variable of interest was a test score, and we want to see if the mean test score for Group A is Larger than Group B. Use alpha = .05...
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