Question

A certain triathlon consists of a ​2.6 mile ​swim, a ​110 mile bicycle​ ride, and a ​26.2mile run. At one​ point, a participant had completed as many miles as the number of miles left to complete. How many miles had he completed at that​ mark?

Answer 1

Let x be the number of miles completed by the participant before the mark. Then, the total distance of the triathlon is:

2.6 + 110 + 26.2 = 138.8 miles

At the mark, the participant has completed x miles and has the remaining distance to complete, which is:

138.8 - x

According to the problem, x is equal to the remaining distance:

x = 138.8 - x

Solving for x, we get:

2x = 138.8

x = 69.4

Therefore, the participant had completed 69.4 miles at the mark.