SOLUTION: A political strategist claims that 55% of voters in Madison County support his candidate. In a poll of 200 randomly selected voters, 98 of them support the strategist's candidate.

Question 320759: A political strategist claims that 55% of voters in Madison County support his candidate. In a poll of 200 randomly selected voters, 98 of them support the strategist's candidate. At = .05, is the political strategist's claim warranted?
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
A political strategist claims that 55% of voters in Madison County support his candidate. In a poll of 200 randomly selected voters, 98 of them support the strategist's candidate. At = .05, is the political strategist's claim warranted?
----------
Ho: p = 0.55 (claim)
Ha: p not equal to 0.55
--------------------------
sample proportion = 98/200 = 0.49
-----
z(0.49) = (0.49-0.55)/sqrt[0.55*0.45/200] = -1.7056
---
p-value = 2*P(z < -1.7056) = 2*normalcdf(-1000,-1.7056) = 0.0881
-------------------
Since the p-value is greater than 5%, faill to reject Ho.
The test results support the claim.
======================================
cheers,
Stan H.
RELATED QUESTIONS
A political strategist claims that 56% of voters in Madison County support his candidate. (answered by CPhill)

A political strategist claims that 56% of voters in Madison County support his candidate. (answered by math_tutor2020)

A political strategist claims that 56% of voters in Madison County support his candidate. (answered by Boreal)

A political strategist believes that at least 58% of voters in a certain state support... (answered by stanbon)

I can't seem to get this at all and would appreciate some help A political strategist... (answered by stanbon)

Poll result show that 53% of voters in a district support a certain candidate for public... (answered by Alan3354)

A candidate for a political office claims that he will win the election. A poll is... (answered by bella88)

The mayor of a town has proposed a plan for the annexation of a new community. A... (answered by proyaop)

In a population where 32% of voters prefer Candidate A, an organization conducts a poll... (answered by Boreal)