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The City of Decatur finds that salaries for residents working in the technology sector follow an...

The City of Decatur finds that salaries for residents working in the technology sector follow an approximately normal distribution with a mean of $42,800 and a standard deviation of $8,365. To the nearest hundredth, what Z-Score would be used to determine the percentage of residents working in the technology sector who earn more than $30,000?

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Answer #1

Solution :

Given that,

mean = = 42800

standard deviation = =8365

P(x >30000 ) = 1 - P(x< 30000)

= 1 - P[(x -) / < (30000-42800) / 8365]

= 1 - P(z <-1.53 )

Using z table

= 1 - 0.0630

= 0.9370

=93.70%

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