The third running track is 12 3/4 meters longer than the second running track. What is the total length of the third running track?

Question

The third running track is 12 3/4 meters longer than the second running track. What is the total length of the third running track?

Answer 1

As long as the second running track in unknown then you let x be equal to the length of the second running track. 

 

Therefore the total length of the third running track in reference to the unknown length would be:

 

x + (12  3/4)