Firefighter Math Applications Questions and Answers Flashcards

Engine pressure must supply 100 psi at the nozzle. Friction loss is 25 psi and there is no elevation change. What is the required pump discharge pressure?

Answer: 125 psi

Pump discharge pressure equals nozzle pressure plus friction loss: 100 plus 25 equals 125 psi.

A crew must stretch 250 feet of 1.75-inch hose. Each 50-foot section weighs 20 lbs. How much hose weight will the crew carry?

Answer: 100 lbs

250 feet divided by 50 feet per section equals 5 sections; 5 times 20 lbs equals 100 lbs.

A water tender carries 3,000 gallons and makes 3 trips, delivering 2,400 gallons each trip and retaining 600 gallons as a reserve. How many total gallons are delivered?

Answer: 7,200

2,400 gallons per trip multiplied by 3 trips equals 7,200 gallons delivered.

A building is 3 stories tall and each story is 10 feet high. What elevation pressure in psi must be added to the pump discharge pressure? (Use 0.434 psi per foot)

Answer: 13.0 psi

3 stories times 10 feet equals 30 feet of elevation; 30 times 0.434 equals 13.02, which rounds to 13.0 psi.

During a drill, a firefighter completes a 400-meter run in 80 seconds. What is their average speed in meters per second?

Answer: 5 m/s

Speed equals distance divided by time: 400 divided by 80 equals 5 meters per second.

If a 100-foot aerial ladder is extended at a 75-degree angle, approximately what vertical height does it reach? (sin 75 degrees equals approximately 0.97)

Answer: 97 feet

Vertical reach equals ladder length times sin of the angle: 100 times 0.97 equals 97 feet.