Question

"slow drivers" contribute to road rage problems and the police officer noticed that 2 of the 150 drivers in her survey caused problems for other drivers because of their slow speed. Use normal distribution and this information to describe a "slow" driver in terms of their speed.

thanks,

Answer 1

With this limited information, I don't know how you can get a normal distribution. You don't know the mean or standard deviation (SD) of car speeds. Do you have some of this information?

However, if there are 1/75 (.01333) as slow drivers, with that proportion at the lowest end of a normal distribution would be equivalent to a Z score of -2.22. (This can be found in a table at the back of most statistics books called areas under the normal distribution, or something like that.)

Assuming a normal distribution for speed (which I doubt exists in reality), using the Z-score formula, if you know either the mean or SD, you can then find the other value.

I hope this helps. If not, repost with further questions. Thanks for asking.