1、0.64*7.2+3.6*2.72
=0.64*2*3.6+3.6*2.72
=3.6*(1.28+2.72)
=3.6*4
=14.4
2、0.78*0.45*0.1/7.8/0.045
=7.8*0.045*0.1/(7.8*0.045)
=0.1