Use the empirical rule to determine the approximate probability that a z value is between 0 and 1 on the standard normal curve.

Question

Use the empirical rule to determine the approximate probability that a z value is between 0 and 1 on the standard normal curve.

1 Answer

Impact of this question

4144 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2015-02-20T18:15:12

You need to use a table of standar normal distribution curve. There are different kind of tables (cumulative, fi function, stc..), but your anwer is:
$P( 0 < z < 1) = 0.34$

The empirical rule allows you to make a quick assessment of probability without using a table. Just memorise these three numbers:

$0.34=34%$ is less than one standard deviation $sigma$ higher than the mean $mu$
$0.135=13.5$ is between $sigma$ and $2sigma$ higher than $mu$
$0.025=2.5%$ is more than $2sigma$ higher than $mu$

The same goes for values below $mu$ , as the normal curve is symmetrical. (So you have 68% of your values between $mu-sigma$ and $mu+sigma$ , or between $z=-1$ and $z=+1$ )

Remember every $sigma$ translates to $1$ on the $z$ -scale

Science

Math

Humanities

... and beyond

Use the empirical rule to determine the approximate probability that a z value is between 0 and 1 on the standard normal curve.

1 Answer

Related questions

Impact of this question