17.4*2.43-1.43*7.4怎样简便计算
问题描述:
17.4*2.43-1.43*7.4怎样简便计算
答
17.4*2.43-1.43*7.4
=10x2.43+7.4x2.43-7.4x1.43
=24.3+7.4x(2.43-1.43)
=24.3+7.4
=31.7