Since there are 26 students in Mr. Carson's class, and each kid gets 3 pencils, that means we will multiply 26 and 3, in which we get 78. Now, since boxes of pencils only contain a dozen, which is 12 pencils, we will divide 78 by twelve, in which we get 6.5 boxes. You can't buy half a box, so he will need 7 boxes, since having 6 boxes means that you don't have enough pencils.
Hope this helps!
Standard error of the mean is computed by:
Standard error = SD/ sqrt N
Where:
N is the sample size
SD is the standard deviation
To get the standard deviation, you need to get the sqrt of
the variance = sqrt 9 = 3
So plugging in our data:
Standard error = 3 / sqrt (16)
= 0.75
We want to find
, where
is a binomial distribution with
and
. So
