1]8.7－1.9－3.1= 0.7×16–16×0.3=2]（12.5＋1.25）×0.8= （5.6＋3.5）÷0.7=3]9.1÷4－3.1÷4= 8.92－0.03－1.97=4]0.175÷0.25÷4= 0.8×0.8×0.5=5]12.5÷0.25＋7.5×4= 42÷4－32×0.25=6]5.6×0.125＋4.4÷8...