Answer
719.325 $\approx$ 719
Work Step by Step
Step 1: Represent With Pythagorean Theorem $378^{2}$ + $612^{2}$ = $c^{2}$
Step 2: Isolate c and Simplify $c^{2}$ = 517428
Step 3: Square Root Both Sides and Simplify $\sqrt (c^{2})$ = $\sqrt (517328)$
c = 719.325 $\approx$ 719