SOLUTION: A standardized exam's scores are normally distributed. In a recent year, the mean test score was 1462 and the standard deviation was 319. The test scores of four students sel
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Question 1182257: A standardized exam's scores are normally distributed. In a recent year, the mean test score was 1462 and the standard deviation was 319. The test scores of four students selected at random are 1890,1180 ,2210,and 1350. Find the z-scores that correspond to each value and determine whether any of the values are unusual.
The z-score for 1890 is____?
Round to two decimal places as needed.) Answer by math_tutor2020(3817) (Show Source):
z = (x - mu)/sigma
z = (1890-1462)/319
z = 1.34 approximately
I would consider this to be not unusual. In other words, it seems fairly likely. Any z score such that would be considered usual; anything outside this interval is considered unusual. Keep in mind that your teacher may use another interval, so I would check with them about that. Though usually, if a z score is further than 2 standard deviations from the mean, then it's considered unusual.
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