## Elementary Algebra

To find the incision in centimeters, we need to multiply 76 millimeters by the ratio that converts millimeters to centimeters. The ratio that converts millimeters to centimeters is $\frac{0.1\ centimeter}{1\ millimeter}$. After all, when multiplied by the original expression, this ratio cancels our the undesired units and leaves us with the desired units, centimeters. So, 76 $\times$ $\frac{0.1\ centimeter}{1\ millimeter}$ = 7.6 centimeters.