Two automobiles travel in the same direction at 40 miles per hour and 50 miles per hour, respectively? How many hours after they are alongside of each other will they be 18 miles apart.

To find out how many hours after the two automobiles are alongside each other they will be 18 miles apart, we can set up a distance equation based on their speeds.

Let's assume that the time both automobiles travel is 't' hours.

The distance traveled by the first automobile can be calculated using the formula: distance = speed × time.

Therefore, the distance traveled by the first automobile is 40t miles.

Similarly, the distance traveled by the second automobile is 50t miles.

According to the problem, when they are alongside each other, the difference between their distances will be 18 miles. Since the first automobile is traveling at a slower speed, its distance traveled will be lower than that of the second automobile.

Setting up the equation: 50t - 40t = 18

Simplifying the equation: 10t = 18

Dividing both sides of the equation by 10, we find that:

t = 1.8

Therefore, after 1.8 hours, the two automobiles will be 18 miles apart when they are alongside each other.

50 t - 40 t = 18