Problem Solving Word Problem

Question

A duathlon consists of a run, a bike ride, and a second run. Use the information below about the average rates of one participant who completed a 55 kilometer duathlon in 2 hours 35 minutes. First run: 12 km/hr, biking: 30 km/hr, second run: 12 km/hr. Write an equation.

Answer 1

Assuming that the two runs were of the same distance (other wise 3 variables need 3 equations)

b represents the time biking

r represents the time running

 

b + r = 2 7/12

30b + 12r = 55

 

 

Now solve the system by elimination or substitution