Question

用简便方法计算下面各题 13.6-1.8-3.213.7+1.98+0.02+5.35.1+0.9-5.1+0.936×9910.75+0.4+0.2538.14-5.46

用简便方法计算下面各题 13.6-1.8-3.213.7+1.98+0.02+5.35.1+0.9-5.1+0.936×9910.75+0.4+0.2538.14-5.46-4.5418.51-9.03-0.9732+6.4+68+3.615.5+26.5-20.41O.27+0.4-8.2724.6-3.98+5.4-6.0264.3-18.75+15.7-11.25．

Answer 1

（1）13.6-1.8-3.2
=13.6-（1.8+3.2）
=13.6-5
=8.6

（2）13.7+1.98+0.02+5.3
=（13.7+5.3）+（1.98+0.02）
=19+2
=21

（3）5.1+0.9-5.1+0.9
=（5.1-5.1）+（0.9+0.9）
=0+1.8
=1.8

（4）36×99
=36×（100-1）
=36×100-36
=3600-36
=3564

（5）10.75+0.4+0.25
=10.75+0.25+0.4
=11+0.4
=11.4

（6）38.14-5.46-4.54
=38.14-（5.46+4.54）
=38.14-10
=28.14

（7）18.51-9.03-0.97
=18.51-（9.03+0.97）
=18.51-10
=8.51

（8）32+6.4+68+3.6
=（32+68）+（6.4+3.6）
=100+10
=110

（9）15.5+26.5-20.4
=42-20.4
=21.6

（10）1O.27+0.4-8.27
=1O.27-8.27+0.4
=2+0.4
=2.4

（11）24.6-3.98+5.4-6.02
=（24.6+5.4）-（6.02+3.98）
=30-10
=20

（12）64.3-18.75+15.7-11.25
=（64.3+15.7）-（11.25+18.75）
=80-30
=50