用简便方法计算 4.56÷12.5÷0.8 3.2×10.1 38×99+38 7/15÷5+8/15×1/5 1-0.225÷0.9-0.75 65×65/66

4.56÷12.5÷0.8 =4.56÷(12.5×0.8)=4.56÷10=0.4563.2×10.1=3.2×(10+0.1)=32+0.32=32.3238×99+38=38×(99+1)=38×100=38007/15÷5+8/15×1/5=7/15×1/5+8/15×1/5=(7/15+8/15)×1/5=1×1/5=1/51-0.225÷0.9-0.7...2.9+29.9+299.9+2999.9写出这个我给你分2.9+29.9+299.9+2999.9=3-0.1+30-0.1+300-0.1+3000-0.1=3333-4*0.1=3332.6