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26. The scores on a standardized math test for 8th grade children form a normal distribution...

26. The scores on a standardized math test for 8th grade children form a normal distribution with a mean of 80 and a standard deviation of 10. (8 points) a. What proportion of the students have scores less than X = 83? b. If samples of n = 6 are selected from the population, what proportion of the samples have means less than M = 83? c. If samples of n = 30 are selected from the population, what proportion of the samples will have means less than M = 83?

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