Word Problem Practice

D=rt Problem:

Bill started biking from his home at 8:00AM at a rate of 16km/h.  His sister Julie started biking from the same house at 8:30AM at a rate of 20km/h.  If they are traveling along the same route, how long is it before Julie overtakes her brother?

HINT (They are heading in the same direction and will travel the same distance!)

CHART:

                  km/h              h                   km

   Bill           16              x + 0.5         16(x+0.5)

   Julie          20                 x                 20x

Equation:  16(x+0.5) = 20x

                   16x +8 = 20x

                           8 = 4x

                            2 = x   <--  Julie's time riding

                         2.5 = x + 0.5  <-- Bill's time riding

Check:

    2h(20km/h) = 40km

    2.5h(16km/h) = 40km

It will take Julie 2 hours to over take Bill on the bike ride.

Be sure to check back later as I will post more problems to help you study!