98×32=(100-2)×32=100×32-2×32=3200-64=3136
98×32=(100-2)32=3200-64=3136
98Ⅹ32 =(100-2)x32 =100Ⅹ32-2x32 =3200-64 =3146
(100-2)x32=3200-64=3136
98x32=100x32-2x32=3200-64=3136