A newspaper report claims that 30% of all tea-drinkers prefer green tea to black tea. Leo is the office manager at a company with thousands of employees. He wonders if the newspaper’s claim holds true at his company. To find out, Leo asks a simple random sample of 125 tea-drinking employees which they prefer: green tea or black tea.
Here's Leo's null hypothesis:The proportion of all tea-drinkers at the company that prefer green tea to black tea is...