STAT 200 Week 6 Homework Problems
Rubric
Correct Answers with no work shown or partial work shown to justify the answer is graded
at 50%.
1.
Many
... [Show More] high school students take the AP tests in different subject areas. In 2007, of the 144,796
students who took the biology exam 84,000 of them were female. In that same year, of the
211,693 students who took the calculus AB exam 102,598 of them were female ("AP exam
scores," 2013). Estimate the difference in the proportion of female students taking the biology
exam and female students taking the calculus AB exam using a 99% confidence level.
Answer:
P1=84000/144796=0.5815
P2=102598/211693=0.4846
n1 =144796, n2=211693
99% confidence interval for difference in p1-p2
=(0.5815-0.4846)+/-1.645*sqrt((0.5815*(1-0.5815)/144796)+(0.4846*(1-0.4846)/211693))
=0.0968+/-0.0028
=(0.0941, 0.0996)
2.
Are there more children diagnosed with Autism Spectrum Disorder (ASD) in states that have
larger urban areas over states that are mostly rural? In the state of Pennsylvania, a fairly urban
state, there are 245 eight year olds diagnosed with ASD out of 18,440 eight year olds evaluated.
In the state of Utah, a fairly rural state, there are 45 eight year olds diagnosed with ASD out of2,123 eight year olds evaluated ("Autism and developmental," 2008). Is there enough evidence
to show that the proportion of children diagnosed with ASD in Pennsylvania is more than the
proportion in Utah? Test at the 1% level.
Answer:
n1=18,440
x1=245
p1=245/18440 = 0.013
q1=1-0.013 = 0.987
n2=2,123
x2=45
p2=45/2123 = 0.021
q1=1-0.021 = 0.979
p-= (245+45)/(18440+2123) = 0.014
q-=1-0.014 = 0.986
z={(0.013+0.021)-0}/sqrt[{(0.014*0.986)/18440}+{(0.014*0.986)/2123}]
z=12.760
3.
All Fresh Seafood is a wholesale fish company based on the east coast of the U.S. Catalina
Offshore Products is a wholesale fish company based on the west coast of the U.S. Table #9.2.5
contains prices from both companies for specific fish types ("Seafood online," 2013) ("Buy sushi
grade," 2013). Do the data provide enough evidence to show that a west coast fish wholesaler is
more expensive than an east coast wholesaler? Test at the 5% level. [Show Less]