Problema Solution

Given the speeds of each runner below, determine who runs the fastest.

Debbie runs 9 feet per second.

Jessica runs 414 feet in 50 seconds.

Emily runs 1 mile in 470 seconds.

Frank runs 603 feet in 1 minute.

Answer provided by our tutors

Debbie runs 9 feet per second: 9 ft/s


Jessica runs 414 feet in 50 seconds: 414/50 ft/s = 207/25 ft/s = 8 7/25 ft/s


Emily runs 1 mile in 470 seconds: since 1 mile = 5280 ft we have 1/470 mi/s = 5280/470 ft/s = 528/47 ft/s = 11 11/47 ft/s


Frank runs 603 feet in 1 minute: 603 ft/min = 603/60 ft/s = 201/20 ft/s = 10 1/20 ft/s


Since:


11 11/47 > 10 1/20 > 9 > 8 7/25


Emily runs the fastest.