Calcul a average for price of cars

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$30 - $250

Project Description:
explanation :

I am creating a script in PHP which need to give a average correct

all this data follow a Gausien repartition ... but some prices are not correct and too lower or too higher... so it dommage the reliability of the average.

As it's a Gaussian curve law... Could you give me the formula to calculate the average price ?

could you help me if i provide you example of data ?

thanks for you help

If you are php coder it's a good advantage.

Skills required:
PHP, Statistics
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