H0: p = 0.20
Ha: p
0.20
Sample proportion
= 6 / 22 = 0.2727
Test statistics
z = (
- p) / sqrt ( p ( 1 - p) / n)
= (0.2727 - 0.20 ) / sqrt ( 0.20 * 0.80 / 22)
= 0.85
p-value = 2 * P(Z > z)
= 2 * P(Z > 0.85)
= 2 * 0.1977
= 0.3954
Since p-value > 0.05 level, Do not reject H0.
This is strong conclusion, since p-value is more away from significance level
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