- #1
Little Bear
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Homework Statement
a. Do the data provide sufficient evidence to indicate that the average verbal score for all California students in the class of 2003 is different from the national average? Test using alpha = .05.
b. Do the data provide sufficient evidence to indicate that the average math score for all California students in the class of 2003 is different from the national average? Test using alpha = .05.
c. Could you use this data to determine if there is a difference between the average math and verbal scores for all California
students in the class of 2003? Explain your answer.
Homework Equations
Relevant DATA:
n = 100 (California students sampled)
national average scores for verbal = 507
sample California average for verbal = 499
standard dev California for verbal = 98
Relevant EQUATION:
z = [sample California average - mean National]
[standard dev Californial for verbal/sqrt(n)]
The Attempt at a Solution
z = [499 - 507]/[98(sqrt(100))]
= -8/9.8
= - 0.816
This answer for part a. is wrong.
Answers at the back of the book:
a. yes; z = -3.33 b. no; z = 1 c. no
I am stuck at part a. My wrong answer is z = -0.816. Please show me how step-by-step to derive at the correct answer. Thank you very much.