A freight train and a passenger train leave a rail yard at the same time and travel on parallel tracks, The passenger train travels 5 mph faster than the freight train. The combined distance traveled
after 3 hours is 135 miles. What is the average speed of the freight train?

A 70 mph
B 20 mph
C 22 mph
D 19 mph

$X = $12y

Step-by-step explanation:

In this question, we are asked to give an expression to represent the amount of money charged to a man who stayed in a motel for a particular number of days.

Firstly, we need to know the amount of money charged per day. This is visible from

the question and it is equal to $y.

Secondly, the number of days/night stayed is 12 days. This means that the amount of money he was charged is 12 * y = $12y

Since the amount of money charged is equal to $x, the amount to pay can be expressed in terms of y and x to be

$X = $12y