Question 1041208
A coin is tossed 200 times and it lands heads up 115 times. At the 5% significance level, is there sufficient evidence to claim that the coin is not equally likely to land heads or tails? 

(a) State the null & alternative hypotheses. 
H0: p = 1/2 
Ha: p # 1/2 (claim)
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p-hat = 115/200 = 0.575
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z(0.575) = (0.575-0.5)/sqrt(0.5^2/200) = 2.1213
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p-value = 2*p(z > 2.1213) = 2*normalcdf(2.1213,100) = 0.0339
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Decision: Since the p-value is less than 5%, Reject H0.
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Interpretation: In Words 
Decision:: The test results support the claim that the
coin is not equally likely to land heads or tails at
the 5% significance level.
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Cheers,
Stan H.
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