Question

脱式计算，能简算的要简算．21÷0.25÷0.43.5×0.7+5.5×0.7+0.7

脱式计算，能简算的要简算．21÷0.25÷0.43.5×0.7+5.5×0.7+0.714.5×1020.125×3.2×0.2564×4.5+3.6×451.58×99+1.58．

Answer 1

（1）21÷0.25÷0.4
=21÷（0.25×0.4）
=21÷0.1
=210

（2）3.5×0.7+5.5×0.7+0.7
=（3.5+5.5+1）×0.7
=10×0.7
=7

（3）14.5×102
=14.5×100+14.5×2
=1450+29
=1479

（4）0.125×3.2×0.25
=（0.125×8）×（0.4×0.25）
=1×0.1
=0.1

（5）64×4.5+3.6×45
=（6.4+3.6）×45
=10×45
=450

（6）1.58×99+1.58
=1.58×（99+1）
=1.58×100
=158