A DIE IS ROLLED 19 TIMES $10 TO CORRECT ANSWER

[kurosh]

A DIE IS ROLLED 19 TIMES, WHAT IS THE STANDARD DEVIATION OF THE NUMBER OF 2'S ROLLED? YOU HAVE 5 MINUTES. WORK NEEDED

[thac]

3.16666666666667

[thac]

[censored] works.

[BigBiceps]

mean = 19/6

variance = 19*5/6/6

standard deviation = sqrt (variance)

sd = 1.62

[BigBiceps]

ie.

sd = sqrt(npq)

where
n=19
p=1/6
q=5/6

[blah_blah]

this is a binomial distribution so sd = sqrt(np(1-p))

p = 1/6
n = 19

sd = 1.624

e: the answer above is incorrect and tells you the variance and not the sd

e2: big biceps edited it to my answer

[seki]

how many sides on the die?

[budblown]

quit doing his homework for him

[ImsaKidd]

The answer is 19. You can get 0 2's or 19 2's. 19-0=19.

[stinkypete]

who cares, its not normally distributed