# Statistics

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A random sample of 50 students has a test score average with a standard deviation of 10.9. Find
the margin of error if c = 0.90.

• Statistics -

Margin of error = + or - 1.645 (sd/√n)

Substitute the values given and determine the margin of error.

(The value of 1.645 was found using a z-table for 90% confidence.)

I hope this helps.

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