5.83*0.99,1.02*6.3,10.2÷2.5这3个简便计算

5.83*0.99
=5.83x1-5.83x0.01
=5.83-0.0583
=5.7717
1.02*6.3
=1x6.3+0.02x6.3
=6.3+0.126
=6.426
10.2÷2.5
=(10.2x4)÷ （2.5x4）
=40.8÷10
=4.08
如果本题有什么不明白可以追问,