A golf path distance marker isn't as helpful as one in the middle of the fairway, because the width of the fairway varies and can add additional distance.
But given that your ball doesn't lie exactly on the line of the distance marker, its still up to you to figure out how much more distance you have to travel. One way is to use an average step to equal one foot and ten steps to equal another 10 feet. A final indicator, given that all three others are missing, is to look for a tree planted at the edge of the fairway--often these are placed at the 100, 150, and 200 yard distances to make a more permanent indicator.
It all sounds like you need a calculator either in your head or on your golf bag in order to keep track and do the math. One final option is to use a Golf Range Finder, as shown in te video. My husband bought a Bushnell Range Finder--his decision was based on the fact that there was a single button pushed in order to get the answer. If you get one, be sure to keep extra batteries on hand.