*** *** U.S. *** wants an estimate *** *** proportion *** *** population *** support *** current
policy *** *** *** *** *** care system. The *** *** the estimate to *** within 0.03 of
the *** *** Assume a 98% level *** *** *** *** political *** estimated *** supporting *** *** policy *** *** *** (Use *** *** Table.)
a.
How large of a sample is required? (Round *** *** *** *** *** places. *** *** *** answer to
the next whole *** large *** *** sample *** *** necessary if no *** were available for *** proportion supporting
current *** *** to estimate the sample *** required *** estimate the *** *** p(1 p)
z E
2
where pis the proportion *** *** *** *** Z
= 2and
Eis the margin of *** Given *** *** 0 *** .
Given *** *** *** *** 0:03. The condence coecient *** Assume *** the proportion *** 0 *** *** *** *** *** ZisZ
= 2= 2
:33 .
The minimum sample size *** *** estimate the proportion is
n= *** p)
z E
2
= 0 :54(1 ***
2:33 0
:03
2
= 1498 *** 1499 :
Thus, *** sample of sizen= *** ensure *** *** *** *** for *** *** *** *** *** of *** *** .
b. Assume that pis unknown. Let *** 0 :5 .
Given *** *** *** *** *** 0 :03 *** *** condence *** *** *** .
The *** value of *** *** 2
:33 .
The *** *** size *** *** *** *** proportion *** *** p)
z E
2
= *** *** 0:5) *** 0
:03
2
= *** :0278
*** *** the sample of sizen= 1509will *** *** *** condence *** *** *** *** will have a
margin *** *** 0:03 ***