Question

Write an equation to model this situation:

Mr. Johnstone began the race 3 feet in front of the start line. He runs a speed of 4.5 miles per hour.

Answer 1

To model Mr. Johnstone's position in the race, we convert his speed from 4.5 miles per hour to 396 feet per minute and use the equation: Position(ft) = 3 ft + (396 ft/min × Time(min)).

Step-by-step explanation:

To model Mr. Johnstone's position during the race, we can write the equation of motion that describes his position as a function of time. Since he begins 3 feet in front of the start line and travels at a consistent speed, we can use the following equation:

Position (ft) = Initial Position (ft) + (Speed (ft/min) × Time (min))

However, we need to convert Mr. Johnstone's speed from miles per hour to feet per minute. There are 5280 feet in a mile and 60 minutes in an hour, thus:

Speed = 4.5 miles/hour × (5280 feet/mile) / (60 minutes/hour) = 396 feet/minute

The equation modeling Mr. Johnstone's position as a function of time is therefore:

Position (ft) = 3 ft + (396 ft/min × Time (min))