Shipping time: An internet company claims that 9% of its orders are shipped within two days. Suppose that last month they received 4000 orders. A consumer group questioning the claim took a random sample of 200 orders and found that 68 were shipped within 2 days. Is this strong enough evidence to conclude that less than 90% of all orders received were shipped within two days? Use a significance level of 5%. Then, qualify your findings range of percentages.
Added by Donald R.
Step 1
State the null and alternative hypotheses: - Null hypothesis (H0): The proportion of orders shipped within two days is equal to or greater than 9% (p >= 0.09). - Alternative hypothesis (Ha): The proportion of orders shipped within two days is less than 9% (p < Show more…
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