POD week 22, Problem One

The Problem

1. A train travels at a constant rate of 55 miles per hour through a tunnel. Forty-five seconds after the front of the train enters the tunnel the front of the train exits the tunnel. How many feet long is the tunnel?

2. The one not being presented, therefore momentarily unimportant (it does not matter right now)

Step ONE

• 1 mile = 5,280 feet• 5,280*55=290,400 feet• 55 miles = 290,400 feet

Step TWO

• 290,400/60=4840 feet • 4,840 fpm (Feet Per Minute)• 4,840/60=80 ⅔• 80 ⅔ fps (Feet Per Second)

Step THREE

• 80 ⅔*45=3,630

The Answer

• The tunnel is 3,630 feet long

Q U E S T I O N S ?