The sum of two consecutive mile markers on the interstate is 561. Find the numbers on the markers.

Let x equal the first mile marker. Write an expression for the second mile marker.

Step-by-step explanation:

Let x equal the first mile marker. Then x + 1 represents the second mile marker.

Then x + (x + 1) = 561, or

2x + 1 = 561, or

2x = 560, and so x = 280

Then the first mile marker reads 280 and the second mile marker reads 281.