israel1machorro
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- Mar 10, 2015
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given a test with mean of 73 and standard deviation of 12:
i) find the probability a result is between 74 and 80.
ii) find the probability result is less than 60.
iii) find the probability a result is more than 90.
iv) find the score that Is larger that 30% of the result.
v) find the scores that on either side of the middle 20% of results.
so what I know is that standard deviation is the (square root: (x - the mean)2 /N-1) however bringing the probability up is the part I am confused on. what type of probability? and i am corporating it to like say between certain numbers 74 and 80.I am new to this so I have no idea sorry lol. there practice problems for me.
i) find the probability a result is between 74 and 80.
ii) find the probability result is less than 60.
iii) find the probability a result is more than 90.
iv) find the score that Is larger that 30% of the result.
v) find the scores that on either side of the middle 20% of results.
so what I know is that standard deviation is the (square root: (x - the mean)2 /N-1) however bringing the probability up is the part I am confused on. what type of probability? and i am corporating it to like say between certain numbers 74 and 80.I am new to this so I have no idea sorry lol. there practice problems for me.
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