Question

I have a sample of 31 7^{th}grade girls who took an IQ
test. I calculated the sample mean to be 105.84 and the
sample standard deviation to be 14.27. Calculate a 95% CI for the
mean.

Answer #1

n = 31

sample mean = 105.84

s = 14.27

t-score for 95% confidence interval = t_{0.025,30} =
2.042

Confidence interval

= (100.606 , 111.074)

In a standardized IQ test the mean score is 100 and
the standard deviation is 15. according to the empirical rule, 95%
of all those who took the test should have scores between

Ten randomly selected people took an IQ test A, and next day
they took a very similar IQ test B. Their scores are shown in the
table below.
Person
A
B
C
D
E
F
G
H
I
J
Test A
104
87
88
110
97
128
116
94
71
101
Test B
110
88
89
108
96
129
119
97
73
106
1. Consider (Test A - Test B). Use a 0.050.05 significance level to
test the claim that...

A sample of 31 IQ scores are selected from 100 IQ scores. Those
scores produce a mean and population standard deviation of 132 and
10, respectively. Find the 95% confidence interval for the annual
average of IQ scores.

Ten randomly selected people took an IQ test A, and next day
they took a very similar IQ test B. Their scores are shown in the
table below.
Person
A
B
C
D
E
F
G
H
I
J
Test A
95
125
100
114
99
91
110
87
73
104
Test B
97
125
102
116
99
90
112
89
75
104
1. Consider (Test A - Test B). Use a 0.010.01 significance level to
test the claim that...

Ten randomly selected people took an IQ test A, and next day
they took a very similar IQ test B. Their scores are shown in the
table below.
Person
A
B
C
D
E
F
G
H
I
J
Test A
106
87
89
102
108
126
113
94
98
78
Test B
111
88
92
101
111
128
112
92
99
79
1. Consider (Test A - Test B). Use a 0.05 significance level to
test the claim that...

We are interested in the mean IQ score of seventh-grade girls in
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selected seventh-grade girls in the district:
114 100 104 89 102 91 114 114 103 105
108 130 120 132 111 128 118 119 86 72
111 103 74 112 107 103 98 96 112 112 93
These scores follow a Normal distribution with standard deviation σ
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Population standard deviation = 12.65724
sample size = 100
How would I test the hypothesis that
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Ten randomly selected people took an IQ test A, and next day
they took a very similar IQ test B. Their scores are shown in the
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Assume that I don't have IQ scores that are normally
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