9.5×10.1
=9.5×10+9.5×0.1
=95+0.95
=95.95
0.25×3.24×4
=（0.25×4）×3.24
=1×3.24
=3.24
0.84×1.7÷0.07
=0.84÷0.07×1.7
=12×1.7
=20.4
7.2÷0.4÷2
=18÷0.2
=90