$解:原式=\frac{1}{5}×7.352-\frac{1}{5}×25×1.072$
$~~~~~~~~~~~~~~~~~=\frac{1}{5}×(7.352-52×1.072)$
$~~~~~~~~~~~~~~~~~= \frac{1}{5}×(7.352-5.352)$
$~~~~~~~~~~~~~~~~~=\frac{1}{5}×(7.35-5.35)×(7.35+5.35)$
$~~~~~~~~~~~~~~~~~=\frac{1}{5}×2×12.7$
$~~~~~~~~~~~~~~~~~=5.08.$