核心提示：0.75＋0.4= 20＋0.78= 4.8＋4.2= 5.7－3= 4.9－1.7= 1.34＋0.8= 2－0.75= 8.7＋0.03= 0.2－0.09= 8.5＋2.5=
3.4－1.4= 0.68＋0.42= 7.82－7.2= 2＋9.1= 0.48
0.75＋0.4= 20＋0.78= 4.8＋4.2= 5.7－3= 4.9－1.7=
1.34＋0.8= 2－0.75= 8.7＋0.03= 0.2－0.09= 8.5＋2.5=
3.4－1.4= 0.68＋0.42= 7.82－7.2= 2＋9.1= 0.48＋0.52=