98×4.2+42×0.2的简便计算

2025-04-24 21:10:32
推荐回答(1个)
回答1:

98*4.2+42*0.2
=98*4.2+4.2*10*0.2
=98*4.2+4.2*2
=(98+2)*4.2
=100*4.2
=420