3.63-1.25+17.37-8.75=(3.63+17.37)-(1.25+8.75)=21-10=1134.42-(4.42-3.87)=34.42-4.42+3.87=30+3.87=33.8710.27+0.4-8.27=10.27-8.27+0.4=2+0.4=2.4