(1)7142.85÷3.7÷2.7×1.7×0.7.
=7142.85÷37÷27×17×7
=7142.85×7÷999×17
=49999.95÷999×17
=50.05×17
=850.85
(2)4.83*0.59+0.41*1.59-0.324*5.9
=4.83*0.59+0.41*(1+0.59)-0.324*(10*0.59)
=4.83*0.59+0.41+0.41*0.59-3.24*0.59
=(4.83+0.41-3.24)*0.59+0.41
=2*0.59+0.41
=1.18+0.41
=1.59
(3)99×1.01×77.78+66.66×33.33
=99×（1+0.01）×77.78+33.33×（2+1）
=99.99×77.78+99.99
=99.99×78.78
=（100-0.01）×78.78=7878-0.7878
(4)37.4×2.7+499×0.73+12.5×0.7
=37.4*2+37.4*0.7+499*0.73+12.5*0.7
=37.4*2+(37.4+12.5)*0.7+499*0.73
=37.4*2+49.9*0.7+499*0.73
=37.4*2+499*0.07+499*0.73
=37.4*2+499*(0.07+0.73)
=37.4*2+499*0.8
=37.4*2+(500-1)*0.8
=37.4*2-0.4*2+400
=37*2+400
=474