Friday

September 19, 2014

September 19, 2014

Posted by **Stuart** on Sunday, February 22, 2009 at 4:06pm.

What proportion of tax preparation fees were between $75 and $115?

A) 0.84

B) 0.34

C) 0.955

D) 0.75

- Statistics -
**MathGuru**, Sunday, February 22, 2009 at 9:48pmThis will be within two standard deviations of the mean. To show this, use z-scores.

Formula is this:

z = (x - mean)/sd

Therefore:

z = (75 - 95)/10 = ?

z = (115 - 95)/10 = ?

I'll let you finish the calculations. Remember that one z-score is below the mean and one is above the mean.

I hope this will help get you started.

**Answer this Question**

**Related Questions**

economics - the average tax charge is $95. Assuming a normal distribution as a ...

Statistics - Assume x is normally distributed with mean µ= 15 and standard ...

Statistics - Suppose that the probability distribution of a random variable x ...

Statistics - I have a problem I need some help on. I have answered parts. Any ...

Statistics - Suppose that the probability distribution of a random variable x ...

MATH - Which of the following normal distributions has the smallest spread? A. A...

Business Statistics - In each case, sketch the two speciﬁed normal curves...

Statistics - The Wechsler Adult Intelligence Scale (WAIS) is a common "IQ test" ...

statistics - Assume a binomial probability distribution has p = .60 and n = 200...

statistics - A normal distribution has a standard deviation equal to 23. What is...