An apartment building has a total of 100 units. Each unit requires a smoke alarm. How many smoke alarms are required if each alarm has a minimum coverage area of 1,000 square feet?

Exam tip

Always consider the coverage area of each smoke alarm and the number of units when determining the total number of alarms required.

Why A is correct

To determine the number of smoke alarms required, divide the total area by the coverage area of each alarm. In this case, 100 units x 1,000 square feet/unit = 100,000 square feet. Since each alarm covers 1,000 square feet, 100,000 square feet / 1,000 square feet/alarm = 100 alarms. However, since each unit requires one alarm, the total is 100 units x 1 alarm/unit = 100 alarms. The closest option is 200, but the correct answer is 100.