67×48+53×67-67怎简便计算 46×78+78×39-85×58怎简便计算
问题描述:
67×48+53×67-67怎简便计算 46×78+78×39-85×58怎简便计算
答
67×48+53×67-67
=67×48+53×67-67×1
=67×(48+53-1)
=67×100
=6700
46×78+78×39-85×58
=78×(46+39)-85×58
=78×85-85×58
=85×(78-58)
=85×20
=1700