5237+3997 =5237+4000-3=9237-3=92346453--1998=6453-2000+2=8453+2=8455 17.42--5.87+2.58--4.13 =(17.42+2.58)-(5.87+4.13)=20-10=109.728/3.2/5=9.72÷(3.2×5)=9.72÷16=0.6075
用简便方法计算 5237+3997 6453--1998 17.42--5.87+2.58--4.13 9.728/3.
5237+3997 =5237+4000-3=9237-3=92346453--1998=6453-2000+2=8453+2=8455 17.42--5.87+2.58--4.13 =(17.42+2.58)-(5.87+4.13)=20-10=109.728/3.2/5=9.72÷(3.2×5)=9.72÷16=0.6075