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

A set of data is normally distributed with a mean of 500 and standard deviation of 40.

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?

## 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 - A set of data is normally distributed with a mean of 455 and a standard ...
- Math - Assume a data set is normally distributed with mean 182 and standard ...
- statistics - The mean of a normally distributed data set is 226.2. The data item...
- statistics - A set of data is normally distributed with a mean of 98 and a ...
- Math-confused...plz help - I. Use Chebyshev’s theorem to find what percent of ...

More Related Questions