此题可这样简便计算：7.25x3.14=（10-2.75）x3.14=31.4-2.75x3.14=31.4-（2+0.75）x3.14=-31.4-6.28-0.75x3.14=31.4-6.28-（0.7x3.14+0.05x3.14）=31.4-6.28-（2.198+0.157）=25.12-2.355=22.765 希望能采纳
