Let's measure a regular sized package of M&M's candy (typically 1.69 ounces). The package you bought has 210 pieces of which 21 are blue.

1.That makes the proportion of m&m's that are blue your sample:p-hat =

If each student used their sample value (sample proportion or p-hat) to make a confidence interval for the percentage of all m&m's that are blue, they might use the formula below to get their interval.

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