Friday

November 21, 2014

November 21, 2014

Posted by **Mary** on Friday, January 16, 2009 at 4:21am.

a). What percent of the data is between 460 and 540?

P(460<x<540)=P(-1<z<1)

=0.8413-0.1587

=0.6826

b). Find the probabilty that a value selected at random is less than 420.

P(x<420)=P(z<(420-500)/40)

=P(z<-2)

=0.0228

are these right?

- Pre-calculus -
**Reiny**, Friday, January 16, 2009 at 8:29amboth correct.

You might find this applet very useful.

http://davidmlane.com/hyperstat/z_table.html

It eliminates the use of charts and tables, you you don't even have to convert to z-scores

**Answer this Question**

**Related Questions**

Pre-calculus - A set of data is normally distributed with a mean of 500 and a ...

math - A set of data is normally distributed with a mean of 16 and a standard ...

Pre-cal - A set of data is normally distributed with a mean of 16 and a standard...

Math - The mean of a set of normally distributed data is 550 and the standard ...

Math - Assume a data set is normally distributed with mean 11 and standard ...

Math - Assume a data set is normally distributed with mean 182 and standard ...

statistics - A set of data is normally distributed with a mean of 98 and a ...

statistics - The mean of a normally distributed data set is 226.2. The data item...

Pre calc - A set of 500 values has a normal distribution. The mean of the data ...

Math-confused...plz help - I. Use Chebyshev’s theorem to find what percent of ...