立即下载 | 限时 免费 下载 |
同类热门下载
简介:
9+99+999+9999
=(10-1)+(100-1)+(1000-1)+(10000-1)
=10+100+1000+10000-4
=11106
489+487+483+485+484+486+488
=490×7-1-3-7-5-6-4-2
=3430-28
=3402
632-156-232
=632-232-156
=400-156
=244
812-593+193
=812-(593-193)
=812-400
=412
1200÷48×4
=1200÷(48÷4)
=1200÷12
=100
45×99+45
=45×99+45×1
=45×(99+1)
=45×100
=4500