（32.8×91-16.4×92-1.75×656）÷0.02
=（32.8×91-32.8×41-1.75×2×328）÷0.02
=（32.8×91-32.8×41-35×32.8）÷0.02
=32.8×（91-41-35）÷0.02
=32.8×15÷0.02
=492÷0.02=24600