Question 179859
A coin was flipped 60 times and came up heads 38 times. 

(a) At the .10 level of significance, is the coin biased toward heads? Show your decision rule and calculations.
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Ho: p = 1/2
Ha: p > 1/2
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p-hat = 38/60 = 0.63333...
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Critical value for one-tail z-test with alpha=10% is z=1.28
Reject Ho if test statistic is greater than 1.28
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Test statistic = z(0.63333) = (0.633333-0.5)/sqrt[(1/2)(1/2)/(60)] = 2.0655
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(b) Calculate a p-value and interpret it.
p-value = P(z>2.0655) = 0.01944
Interpretation: Less than 1.944% of test results could provide stronger 
evidence for rejecting Ho.
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Cheers,
Stan H.