Question

计算能简算的要简算0.25×3.2×1.25 1.25×3.47×0.8-2.3 3.8×41-3.87.6×...

计算能简算的要简算0.25×3.2×1.25 1.25×3.47×0.8-2.3 3.8×41-3.87.6×9.9 5.16+3.5×2.4 1.9×2.5+25×0.21

Answer 1

（1）0.25×3.2×1.25     
=0.25×4×0.8×1.25
=（0.25×4）×（0.8×1.25）
=1×1
=1；

（2）1.25×3.47×0.8-2.3
=1.25×0.8×3.47-2.3
=1×3.47-2.3
=3.47-2.3
=1.17；

（3）3.8×41-3.8
=3.8×（41-1）
=3.8×40
=152；

（4）7.6×9.9
=7.6×（10-0.1）
=7.6×10-7.6×0.1
=76-0.76
=75.24；

（5）5.16+3.5×2.4
=5.16+8.4
=13.56；

（6）1.9×2.5+25×0.21
=1.9×2.5+2.5×2.1
=2.5×（1.9+2.1）
=2.5×4
=10．