Question

which of the following describes a unit rate? 55 miles in 3 hours; 13 pounds per 12 inches; 24 hours per day; 15 fish per 12 gallons

Explanation:

Step1: Recall unit rate definition

A unit rate is a rate with a denominator of 1 (per 1 unit of the second quantity).

Step2: Analyze each option

• "55 miles in 3 hours": Denominator is 3, not 1.
• "13 pounds per 12 inches": Denominator is 12, not 1.
• "24 hours per day": Denominator is 1 (per 1 day), so this is a unit rate.
• "15 fish per 12 gallons": Denominator is 12, not 1.

Answer:

1. 24 hours per day