Police Math Speed, Distance, and Time Flashcards

A patrol car travels 3 miles north then 4 miles east. What is the straight-line distance from the start?

Answer: 5 miles

By the Pythagorean theorem, √(3² + 4²) = √25 = 5 miles.

A car at 55 mph needs to slow to 25 mph over 10 seconds. What is the average deceleration in mph per second?

Answer: 3 mph/s

Speed drops 30 mph over 10 seconds = 3 mph per second.

A delivery route is 84 miles. Driving at 56 mph with a 15-minute stop, what is the total trip time?

Answer: 1 hour 45 min

Driving time = 84 ÷ 56 = 1.5 hours; plus 15 minutes = 1 hour 45 minutes.

Two cars travel the same direction at 65 mph and 50 mph. How fast does the gap between them grow?

Answer: 15 mph

The gap grows at the speed difference: 65 - 50 = 15 mph.

A car travels 150 miles in 2 hours 30 minutes. What is its average speed?

Answer: 60 mph

2 hours 30 minutes = 2.5 hours; 150 ÷ 2.5 = 60 mph.

At 80 ft/s, approximately how many mph is a car traveling? (1 mph ≈ 1.467 ft/s)

Answer: 55 mph

80 ÷ 1.467 ≈ 54.5, which rounds to about 55 mph.

A patrol car must travel 100 miles. It drives the first 50 miles at 50 mph and must finish the whole trip averaging 50 mph. At what speed must it drive the second 50 miles?

Answer: 50 mph

To average 50 mph over 100 miles the total time must be 2 hours, and the second 50 miles must also be driven at 50 mph.