A car travels 200 miles in the same time that a train travels 300 miles. The speed of the train is 20 miles per hour more than the speed of the car. Which equation could be used to determine the speed of the car, r, in miles per hour?
the equation is time= distance/rate and the train is going 300 miles the car is going 200 miles the train goes 20 miles faster than the car fitting the numbers into the equation 200/r=300/(r+20) cross multiply 200/r = 300/(r+20) 200(r+20) = 300r distributive property 4000+200r=300r subtract 200r from both sides to add like terms 4000=100r divide 100 from each side to get r by itself 40 = rate of car 60 = rate of train