Let's say that we're studying household size in Kings County. The mean HH size is 4.2 persons, with a standard deviation of 1.8 persons.
You can compute the area under the normal curve here: http://www.stat.berkeley.edu/~stark/SticiGui/Text/clt.htm#normal_curve
What is the probability of:
(1) drawing a sample of 1,000 HHs with a mean size of 4.4 persons or more?
(2) drawing a sample of 900 HHs with a mean size between 4.5 and 5?
(3) drawing a sample of 1,500 HH with a mean size of 3.8 or less?
(4) drawing a sample of 600 HHs with a mean size of 4.1 or more?
(5) drawing a sample of 800 HHs with a mean size of 4.3 or less?
(6) drawing a sample of 1,200 HHs with a mean size between 4.4 and 4.6?
Comments
JAKE AND AND EENES NEGLA AND ANNA ONCE AGAIN THE DREAM TEAM
SIGMA of sample= 1.8/sqrt(800)
SIGMA sample= .063
z=(4.3-4.2)/.063
z=1.587
ELISA N, ALESSIA, SAMIR, LIZ B., BRANDON
1.8/sqrt(1000) = 0.056921
z=4.2-4.4/0.0.56=-3.57
99.98%
Joyce, Travis, Gregory
Z=5
Z=13.3
Kentonb, Ahmed Diallo
mean 42
standard 1.8
size 4.1
1.8/sqrt(600)=0.0734
z=4.1-4.2/0.0734=-1.36
91.31%
Marta C. Brenda R.
1.8/sqrt(1,500)= .046
3.8-4.1/.046=-8.69
=0%