You add the three sides together. The problem does help you itself.
"<span>The perimeter of a triangle can be found by adding the lengths of its three sides. "
Convert 5 3/4 to decimal form, to make it easier to solve.
5 3/4= 5.75
3.4+5.75+7.32= 16.47 inches</span>
0.74 is less than 0.79 0.74<0.79