1)
2) The number of success and the number of failures should have 10 in order use a large sample confidence interval.
3) p* = 0.5
At 90% confidence level, the critical value is z0.05 = 1.645
Margin of error = 0.02
4) H0: P < 0.5
Ha: P > 0.5
= 61/100 = 0.61
P-value = P(Z > 2.2)
= 1 - P(Z < 2.2)
= 1 - 0.9861
= 0.0139
Since the P-value is less than the significance level(0.0139 < 0.05), so we should reject the null hypothesis.
At 0.05 significance level, there is sufficient evidence to conclude that a majority of seniors think their job prospects are good.
5) The 95% confidence interval is
1.(10) Assume that the proportion of successes in a population is p. If simple random samples...
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