my final is in a few hours
#help me
gloomy jackal
neat shoreBOT
my final is in a few hours
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fair root
my final is in a few hours
you know the variance is sigma^2 and you (should) know Var(X) = E(X^2)-E(X)^2
so sigma^2 = E(X^2)-E(X)^2.
Now E(X^2) is given as 10, and what is E(X) equivalent to? Does this help you further?
gloomy jackal
yes but how am i supposed to get the value of mew
fair root
Knowing some common values help as well. 0.1587 is a common probability, of being at least one sigma higher then the average
since this is the case for 4, we now know that the mu is sigma lower then 4, so
$\mu = 4-\sigma$
jade portalBOT
Jehare
gloomy jackal
ohh i think i get it now
fair root
ohh i think i get it now
I basically gave you the two equations you need to solve. You should get a quadratic with two pairs of different integer solutions. You got that?
gloomy jackal
yes yes thank you
white copperBOT
@gloomy jackal