The distance d a train travels varies directly with the amount of time t that has elapsed since departure. If the train travels 475 miles in 9.5 hours, how many miles did the train travel after 4 hours?
We are told that the distance d a train travels varies directly with the amount of time t that has elapsed since departure. We can write this as an equation: d = kt, where k is the constant of variation.
To find the value of k, we can use the information that the train travels 475 miles in 9.5 hours. Plugging these values into the equation, we get 475 = k * 9.5. Dividing both sides of the equation by 9.5, we find that k = 475/9.5 = 50.
Now that we have the value of k, we can find the distance the train traveled after 4 hours. Plugging 4 into the equation, we get d = 50 * 4 = 200.
Therefore, the train traveled 200 miles after 4 hours.