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Question
Consider the relative frequency distribution given below:| Class Interval | Relative Frequency |
| 20-under 40 | 0.2 |
| 40-under 60 | 0.3 |
| 60-under 80 | 0.4 |
| 80-under 100 | 0.1 |
There were 60 numbers in the data set. How many numbers were in the interval 20-under 40?
a) 12
b) 20
c) 40
d) 10
e) 15
Answer
This answer is hidden. It contains 1 characters.
Related questions
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Q:
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Q:
The mean square error (MSerr) is calculated by dividing the sum of squares error (SSerr) by the number of error degrees of freedom (dferr).
Q:
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0.292143
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0.013231
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df
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MS
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1
3.550325
3.550325
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4
0.224675
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5
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Q:
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1
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4
0.224675
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5
3.775 Annie's sample size is __________.
a) 2
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Q:
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Q:
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Q:
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Q:
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Q:
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Q:
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Q:
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Q:
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a) reject the null hypothesis 12 = 22
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Q:
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a) 3.68
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c) 3.50
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Q:
A random sample of 400 items from a population shows that 160 of the sample items possess a given characteristic. A random sample of 400 items from a second population resulted in 110 of the sample items possessing the characteristic. Using this data, a 99% confidence interval is constructed to estimate the difference in population proportions which possess the given characteristic. The resulting confidence interval is _______.
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Q:
A researcher is interested in estimating the difference in two population proportions. A sample of 400 from each population results in sample proportions of .61 and .64. A 90% confidence interval for the difference in the population proportions is _______.
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c) -0.11 to 0.05
d) -0.07 to 0.01
e) -0.08 to 0.12
Q:
Maureen McIlvoy, owner and CEO of a mail order business for wind surfing equipment and supplies, is reviewing the order filling operations at her warehouses. Her goal is 100% of orders shipped within 24 hours. In previous years, neither warehouse has achieved the goal, but the East Coast Warehouse has consistently out-performed the West Coast Warehouse. Her staff randomly selected 200 orders from the West Coast Warehouse (population 1) and 400 orders from the East Coast Warehouse (population 2), and reports that 190 of the West Coast Orders were shipped within 24 hours, and the East Coast Warehouse shipped 372 orders within 24 hours. Assuming = 0.05, the appropriate decision is ___________________.a) do not reject the null hypothesis 1- 2= 0b) do not reject the null hypothesis p1- p2= 0c) reject the null hypothesis 1- 2= 0d) reject the null hypothesis p1- p2= 0e) do not reject the null hypothesis p1- p20
Q:
Maureen McIlvoy, owner and CEO of a mail order business for wind surfing equipment and supplies, is reviewing the order filling operations at her warehouses. Her goal is 100% of orders shipped within 24 hours. In previous years, neither warehouse has achieved the goal, but the East Coast Warehouse has consistently out-performed the West Coast Warehouse. Her staff randomly selected 200 orders from the West Coast Warehouse (population 1) and 400 orders from the East Coast Warehouse (population 2), and reports that 190 of the West Coast Orders were shipped within 24 hours, and the East Coast Warehouse shipped 372 orders within 24 hours. Assuming a= 0.05, the observed zvalue is ___________________.
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b) 2.42
c) 1.53
d) 0.95
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