Posted by **Lori** on Saturday, April 17, 2010 at 11:18pm.

The total amount being spent on personal calls in a month by employees of a company follows a normal distribution with a mean of $900 and a standard deviation of $50. Find the probability that in a randomly selected month the amount spent on personal calls is less than $750

- Math -
**MathMate**, Sunday, April 18, 2010 at 7:48am
The standard deviation, σ, is $50. The mean is $900.

To spend less than $750 means that the spending is less than mean - 3σ.

The probability of this happening, assuming the spending follows the normal distribution curve, can be found from the normal distribution tables, for example:

http://www.math.unb.ca/~knight/utility/NormTble.htm

where the probability for the tail end of 3σ is 0.001350, or 0.135%.

## Answer This Question

## Related Questions

- PROBABILITY - The total amount being spent on personal calls in a month by ...
- Statistics - A shoe store knows that the purchase amount by its customers is a ...
- Math - Suppose a brewery has a filling machine that fills 12 ounce bottles of ...
- Math - A normal distribution has a mean of 20 and a standard deviation of 3.What...
- algebra - A normal distribution has a mean of 98 and a standard deviation of 6. ...
- Math - Suppose a brewery has a filling machine that fills 12 ounce bottles of ...
- statistics - A popular retail store knows that the purchase amounts by its ...
- stats - A popular retail store knows that the purchase amounts by its customers ...
- stats - One company produces movie trailers with mean 150 seconds and standard ...
- distribution - In a school, the IQ scores of the students have a normal ...

More Related Questions