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3 years ago

A final statistics exam had a mean of 70 and a variance of 25. If Bruce earned an 80 on his exam, what is his score?

Mathematics

1 answer:

vodka [1.7K]3 years ago

3 0

Answer:

Step-by-step explanation:

Value = 80

Mean = 70

Variance = 25

Standard deviation=root(Variance)=root(25)=5

z score = (value - mean)/standard deviation

= (80-70)/5

= 10/5

= 2

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