Cho is driving a car. He gets to his destination, which is 72 miles away, in 1 hour and 30 minutes.
a. The equation d=rt can be used to model Cho's drive, where d us the distance traveled, r is the speed of the car and, and t is the amount of time spent traveling. Substitute Cho's time and distance into the equation.
72 = 90 (is this correct)
b. Solve the equation in part a to find Cho's speed. Show your work
A. Yeah, almost. :)
d = rt
Since d = 72 miles and t = 1.5 hours or 90 minutes,
72 = 1.5r (if you want r to have units in miles/hour)
72 = 90r (if you want r to have units in miles/minute)
B.
72 = 1.5r
r = 72/1.5
r = 48 miles/hour
72 = 90r
r = 72/90
r = 0.8 mile/min
what is r
a. To substitute Cho's time and distance into the equation d = rt, we need to convert the given time into a decimal format. Cho traveled for 1 hour and 30 minutes, which is 1.5 hours (since there are 60 minutes in an hour). Now, we can substitute the values into the equation:
d = rt
72 = r * 1.5
b. To solve the equation in part a and find Cho's speed, we can divide both sides of the equation by 1.5:
72 / 1.5 = r * 1.5 / 1.5
This simplifies to:
48 = r
Therefore, Cho's speed is 48 miles per hour.