1) 18.3*0.5-5.81*0.5 2) 2.07*0.7+2.07*7.2 3) 38.6*1.8+1.8*2.7 4) 10.27*5.1+8.3*5.1 5)2.3*9.5-7.2*2.3 6) 0.4*5.1+6.9*0.4