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The average teacher's salary in North Dakota is $35,441. Assume a normal distribution with =σ$5100. Round the final answers to at least 4 decimal places and round intermediate z-value calculations to 2 decimal places.What is the probability that a randomly selected teacher's salary is greater than $37,800?=P>X37,800

User Vince Horst
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1 Answer

16 votes
16 votes

ANSWER

0.3228

Step-by-step explanation

We want to find,


P(X>37800)

But since X is normally distributed, we have to find the z-score for a standard normal distribution,


z=(x-\mu)/(\sigma)=(37800-35441)/(5100)\approx0.46

So the probability we can find in the standard normal distribution table is,


P(Z>0.46)

In the z-score table, we have to find z = 0.46,

The table shows the probability that z is less than that value. We want to find the probability that z is greater than that value. This is,


P(Z>0.46)=1-P(Z<0.46)=1-0.6772=0.3228

The probability that a teacher's salary is greater than $37,800 is 0.3228.

The average teacher's salary in North Dakota is $35,441. Assume a normal distribution-example-1
User Shmuli
by
3.0k points
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