normal distribution help

Question

jessicawade · Answer

a set of data has a normal distribution with a mean of 50 and a standard deviation of 8.  what percent of the data should fall between 42 and 58?

jessicawade · Answer

95.5%
68%
47.5%
34%

jessicawade · Answer

normal distribution is the only one im havonmg trouble with sorry lol

amistre64 · Answer

how many standard deviations from the mean are the 'endpoints' ?

jessicawade · Answer

what do you mean? like where does it stop?

amistre64 · Answer

we have a distance, mean to a stated end point: 50 to 58,  how many standard deviations (a standard deviation is defined as being 8 units) are between 50 and 58?  how many standard deviations are between 42 and 58?

jessicawade · Answer

sorry hold on im terrible with math

amistre64 · Answer

this concept is called a z score, which simply tells us the number of standard deviations that fit into a given interval from the mean:$$z=\frac{x-mean}{sd}$$

jessicawade · Answer

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