简算怎么做,谢谢

2025-03-28 18:30:38
推荐回答(1个)
回答1:

27×99
=27×100-27×1
=2700-30+3
=2673
28×250
=250×4×7
=1000×7
=7000
98×303
=100×303-2×303
=30300-606
=29694
49+49×49
=49×1+49×49
=49×(1+49)
=(50-1)×50
=2500-50
=2450