(1)5.03-2.5+0.96, =2.53+0.96, =3.49; (2)35.72-(5.9+5.72), =35.72-5.9-5.72, =35.72-5.72-5.9, =30-5.9, =24.1; (3)25-4.7+5.3, =20.3+5.3, =25.6; (4)1.3+2.83+8.7+0.17, =(1.3+8.7)+(2.83+0.17), =10+3, =13; (5)2.47-2.2-3.8+7.53, =(2.47+7.53)-(2.2+2.8), =10-5, =5. |