a, \(3332:\left(4.49\right)=3332:196=17\)
b, \(72.3.125=\left(72.125\right).3=9000.3=27000\)
c, \(123:1,3+123:7,8+123:0,9=123:\left(1,3+7,8+0,9\right)=123.10=1230\)
d, \(15.24+15.57+81.29+81.56=15\left(24+57\right)+81\left(29+56\right)=15.81+81.85=81\left(15+85\right)=81.100=8100\)