the data given below are from a discrete distribution with positive integer values.there are two values which are unknown, namely "a" and "b".(adsbygoogle = window.adsbygoogle || []).push({});

8,5,3,6,5,9,a,b

if the mean and varience respectively are 6.5 and 7.75, what are the possible values of "a" and "b"?

so far i have that a+b=16 since 3+5+5+6+8+9+a+b/8=6.5 and 6.5x8=64

3+5+5+6+8+9=36 and 64-36=16

i know that the square root of 7.75=2.783882...=standard deviation,but i don't know what to do with this information in order to find a and b

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# Homework Help: Finding two unknowns from varience and mean

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