Task# How Fast is Usain Bolt?

Illustrative MathematicsVaries

This task involves a multi-step conversion between two rates, going from meters per second to miles per hour. In this case, the units coming from the 100 meter race are meters per second and we do not have a good intuition for what this means in miles per hour. Most of us are used to thinking about speeds in terms of miles per hour since the speedometers in our automobiles use these units, so it is good for students to be able to convert between miles per hour and other units for speed that naturally come up. The first solution shows all units in the calculations and does not make any calculations until the end.