1) Ages: 20, 30, 40, 40, 50, 60:

1. Calculate the Mean
2. Calculate the Variance
3. Calculate the Standard Deviation
4. Calculate the Z-scores for each age value.
5. After calculating the z-score for age =50, and by using the normal table (z-table) what proportion of respondents are below Age 50?

Z1 =

Z2 =

Z3 =

Z4 =

Z5 =

Z6 =

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2) Given that the mean age at first marriage for respondents in a survey is 23.33, with a standard deviation of 6.13. Calculate the observed age (raw score) at first marriage associated with a Z score of -0.72.

Observed age at first marriage associated with a Z score of -0.72 = ____________

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3) The mean number of daily cups of coffee for college student respondents in a survey is 4.76 with a standard deviation of 4.18. Calculate the Z score associated with four cups of coffee.

The Z score associated with four cups of coffee = ____________________

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4) Scores for an exam are normally distributed with a mean of 235 and a standard deviation of 52. What is the percentile rank of a raw score 287?

The percentile rank of a raw score 287 = ______________________

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