hi how do you do digital friends? Here ya go...

today we are on tutorial 3.5 on page 126 in our little math book and this unit we are learning the normal approximation to a binomial distribution. here is some things we have learned on Friday the 13th.

The bigger the value of n the harder the binompdf and the closer the normal approximation is to the correct value.

Rule: if N P Q is greater than 10 then use the normal approximation to the binomial distribution.

P129
example

n= 650
p=.048
q=.952 100%-4.8%=95.2%

npq 650(.048)(.952)=29.7>10 its OK! guys


mean=650(.048)=31.2
standard deviation= square npq square 29.7=5.45

z=x-m/standard deviation 30-31.2/5.45=-.22

draw the graph

shade norm(-.22,5)= .587=58.7%

how did we do it?
here we go!

step 1: determine npq *remember q=1-p
step 2: determine if npq is bigger than 10
step 3: determine mean and standard deviation * remember mean = np
and standard deviation = square npq
step 4: calculate appropriate z score * remember z=x-m/standard deviation
step 5: just draw the graph
step 6: use shade norm appropriately

thats all remember to do page 1-8 on page # 130



holla