101X9.87 =(100+1)×9.87=100×9.87+9.87=987+9.87=996.87 1.25X0.25X3.2=(1.25×0.8)×(0.25×4)=1×1=1 200.2X7.8一7.8X0.2=(200.2-0.2)×7.8=200×7.8=156