GROWTH DEVELOPMENT CHILD
MEASUREMENT OF INTELLIGENCE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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He’d better start studying.
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He did better than EVERYONE.
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He scored 2.5 standard deviations above the average.
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He did terrible.
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Detailed explanation-1: -Adam’s Z-score on a test is +2.5. What does this mean? He did better than EVERYONE. He scored 2.5 standard deviations above the average.
Detailed explanation-2: -In Adam’s case, his z-score is +2.5, which means that he scored 2.5 standard deviations above the average.
Detailed explanation-3: -Since 85 is 85-60 = 25 points above the mean and since the standard deviation is 10, a score of 85 is 25/10 = 2.5 standard deviations above the mean. Or, in terms of the formula, A z table can be used to calculate that . 9938 of the scores are less than or equal to a score 2.5 standard deviations above the mean.
Detailed explanation-4: -For example, a Z of-2.5 represents a value 2.5 standard deviations below the mean. The area below Z is 0.0062.
Detailed explanation-5: -Therefore, 98.76% of the area of standard normal distribution is within 2.5 standard deviation of the mean.