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A students received a score of 50 on his history test. The test had a mean of 69 and a standard deviation of 10. Find the z score and assess whether his score is considered unusual.

1.90; unusual

–1.90; not unusual

–1.90; unusual

1.90; not unusual

User Eoldre
by
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2 Answers

3 votes

Answer: The Z-score = - 1.90 unusual

Explanation:

User Fdny
by
8.4k points
7 votes

Answer:

c) The Z-score = - 1.90 unusual

Explanation:

Explanation:-

Let 'X' be the random variable in normal distribution

Given student received a score X = 50

Mean of the Population x⁻ = 69

standard deviation of the Population 'σ' = 10

now


Z = (x^(-)-mean )/(S.D)


Z = (x^(-)-mean )/(S.D) = (50 -69)/(10) = - 1.90

The Z-score = - 1.90

Conclusion:-

The Z-score = - 1.90 unusual

User Kunal Chawla
by
7.3k points

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