用加法交换律与结合律先求出整数，再算结果。4.37+0.28+1.63+5.72＝（4.37+1.63）+（0.28+5.72）＝6+6＝12
4.37+ 0.28 +1.63+ 5.7=(4.37+1.63)+( 0.28 + 5.7)=6+5.98=11.98
