Are my answers below correct Thanks In a survey of 688 US ad
Are my answers below correct? Thanks.
In a survey of 688 US adults with children, 249 of them reported that they saved money for their children’s college education. Can you conclude that more than one third (33%) of US adults with children have saved money for college? Use a 0.05 significance level.
p0 = 0.33
x = 249
n = 688
p1 = x / n = 0.362
a. State the null (H0) and alternative (H1) hypotheses.
H0: p = 0.33
H1: p > 0.33
b. Give the test statistics and the p-value for this significance test.
Standard Error: (Square Root) (p0 (1 - p0) / n)
(Square Root) (0.33 (1 - 0.33) / 688) = .01793
Test Statistic: z = (p1 - p0) / Standard Error
z = (.362 - .33) / .01793 = 1.785
P_value: = P (Z > 1.785)
= 1 - P (Z < 1.785)
= 1 - .9629 = .0371
c. Make a decision on whether or not to reject the null hypothesis.
P_value < 0.05, therefore we reject H0
d. Summarize the conclusion in the context of this problem.
More than 33% of adults have saved money for their children’s college.
Solution
Set Up Hypothesis
 Null, H0:P=0.33
 Alternate, H1: P>0.33
 Test Statistic
 No. Of Success chances Observed (x)=249
 Number of objects in a sample provided(n)=688
 No. Of Success Rate ( P )= x/n = 0.3619
 Success Probability ( Po )=0.33
 Failure Probability ( Qo) = 0.67
 we use Test Statistic (Z) for Single Proportion = P-Po/Sqrt(PoQo/n)
 Zo=0.36192-0.33/(Sqrt(0.2211)/688)
 Zo =1.7805
 | Zo | =1.7805
 Critical Value
 The Value of |Z | at LOS 0.05% is 1.64
 We got |Zo| =1.781 & | Z  | =1.64
 Make Decision
 Hence Value of | Zo | > | Z | and Here we Reject Ho
 P-Value: Right Tail - Ha : ( P > 1.78051 ) = 0.0375
 Hence Value of P0.05 > 0.0375,Here we Reject Ho
ANS:
 More than 33% of adults have saved money for their children’s college


