8th Grade Performance Task
Contributed by: New Standards

Core elements of performance

This task requires students to use their understanding of conversion factors to compare measurements in different units. There are numerous correct approaches.

In a strong response students will use the given equivalents among the three units to express distances in a common unit. This can be done by taking the given equivalent and constructing other equivalents (as in solution #1 below), or it can be done by finding and using conversion factors (as in solution #4 below).

A correct solution

The task gives us this equivalent: one-half lap = 1/8 mile.
Therefore, 1 lap = 1/4 mile = 0.25 mile.

The task also gives us this equivalent: one-half lap = 0.2 km.
Therefore, 1 lap = 0.4 km.

For comparison, we can use these 1 lap equivalents to convert all distance to laps.

Carrie's distance in laps is given: 14 laps

So Carrie ran the farthest and Gina ran the shortest distance.