# Question: A coin was flipped 12 times and came up heads

A coin was flipped 12 times and came up heads 10 times.

(a) Would we be justified in assuming that the sample proportion p is normally distributed? Explain.

(b) Calculate a p-value for the observed sample outcome, using the normal distribution. At the .05 level of significance in a right-tailed test, is the coin biased toward heads?

(c) Use Excel to calculate the binomial probability P(X ≥ 10 | n = 12, π = .50) = 1 – P(X ≤ 9 | n = 12, π = .50).

(a) Would we be justified in assuming that the sample proportion p is normally distributed? Explain.

(b) Calculate a p-value for the observed sample outcome, using the normal distribution. At the .05 level of significance in a right-tailed test, is the coin biased toward heads?

(c) Use Excel to calculate the binomial probability P(X ≥ 10 | n = 12, π = .50) = 1 – P(X ≤ 9 | n = 12, π = .50).

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