一些数奥简便运算题!(见补充)要有完整的过程和答案!9+99+999+9999+99999199999+19999+1999+199+9(1+3+5+…+1989)-(2+4+6+…+1988)389+387+383+385+384+386+388(4942+4943+4938+4939+4941+4943)\654+99*99+459999*2222+3333*333
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![一些数奥简便运算题!(见补充)要有完整的过程和答案!9+99+999+9999+99999199999+19999+1999+199+9(1+3+5+…+1989)-(2+4+6+…+1988)389+387+383+385+384+386+388(4942+4943+4938+4939+4941+4943)\654+99*99+459999*2222+3333*333](/uploads/image/z/8235384-24-4.jpg?t=%E4%B8%80%E4%BA%9B%E6%95%B0%E5%A5%A5%E7%AE%80%E4%BE%BF%E8%BF%90%E7%AE%97%E9%A2%98%21%EF%BC%88%E8%A7%81%E8%A1%A5%E5%85%85%EF%BC%89%E8%A6%81%E6%9C%89%E5%AE%8C%E6%95%B4%E7%9A%84%E8%BF%87%E7%A8%8B%E5%92%8C%E7%AD%94%E6%A1%88%219%2B99%2B999%2B9999%2B99999199999%2B19999%2B1999%2B199%2B9%EF%BC%881%2B3%2B5%2B%E2%80%A6%2B1989%EF%BC%89-%EF%BC%882%2B4%2B6%2B%E2%80%A6%2B1988%EF%BC%89389%2B387%2B383%2B385%2B384%2B386%2B388%EF%BC%884942%2B4943%2B4938%2B4939%2B4941%2B4943%EF%BC%89%5C654%2B99%2A99%2B459999%2A2222%2B3333%2A333)
一些数奥简便运算题!(见补充)要有完整的过程和答案!9+99+999+9999+99999199999+19999+1999+199+9(1+3+5+…+1989)-(2+4+6+…+1988)389+387+383+385+384+386+388(4942+4943+4938+4939+4941+4943)\654+99*99+459999*2222+3333*333
一些数奥简便运算题!(见补充)要有完整的过程和答案!
9+99+999+9999+99999
199999+19999+1999+199+9
(1+3+5+…+1989)-(2+4+6+…+1988)
389+387+383+385+384+386+388
(4942+4943+4938+4939+4941+4943)\6
54+99*99+45
9999*2222+3333*3334
1999+999*999
求(1988*9)*(1988*9)*(1988*9)的末位有多少个0
一些数奥简便运算题!(见补充)要有完整的过程和答案!9+99+999+9999+99999199999+19999+1999+199+9(1+3+5+…+1989)-(2+4+6+…+1988)389+387+383+385+384+386+388(4942+4943+4938+4939+4941+4943)\654+99*99+459999*2222+3333*333
1.
9+99+999+9999+99999
=10+100+1000+10000+100000-1-1-1-1-1
=111110-5
=111105
2.
199999+19999+1999+199+9
=200000+20000+2000+200+9-4
=222200+5
=222205
3.
(1+3+5+…+1989)-(2+4+6+…+1988)
=(1-2)*995
=-995
4.
389+387+383+385+384+386+388
=(389+383)*7/2
=2 702
5.
(4942+4943+4938+4939+4941+4943)\6
=(4939+4943)*6/2/6
=(4939+4943)/2
= 4 941
6.
54+99*99+45
=9*6+9*5+99*99
=9*11+99*99
=99*1+99*99
=99*100
=9900
7.
9999×2222+3333×3334
=3333*6666+3333*3334
=3333*(6666+3334)
=3333*10000
=33330000
8.
1999+999*999
=1999+(1000-1)*(1000-1)
=1000000
9.
(1988*9)*(1988*9)*(1988*9)个位是
8*9*8*9*8*9 没有0
9+99+999+9999+99999
=10+100+1000+10000+100000-5
=111110-5
=111105
199999+19999+1999+199+9
=200000+20000+2000+200+10-5
=222205
(1+3+5+…+1989)-(2+4+6+…+1988)
=(1-2)+(3-4+...
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9+99+999+9999+99999
=10+100+1000+10000+100000-5
=111110-5
=111105
199999+19999+1999+199+9
=200000+20000+2000+200+10-5
=222205
(1+3+5+…+1989)-(2+4+6+…+1988)
=(1-2)+(3-4+...+(1987-1988)+1989
=(-1)+(-1)+....+(-1)+1989
=(1988/2)x(-1)+1989
=-994+1989
=995
389+387+383+385+384+386+388
=390x7-(1+3+7+5+6+4+2)
=2730-28
=2702
(4942+4943+4938+4939+4941+4943)\6
=[4942x6+(1-4-3-1+1)]/6
=[4942x6-6]/6
=4942-1
=4941
54+99*99+45
=(54+45)+99*99
=99+99*99
=(99+1)*99
=9900
9999*2222+3333*3334
=3333*3*2222+3333*3334
=3333(6666+3334)
=3333x10000
=33330000
1999+999*999
=1000+999+999*999
=1000+999*(999+1)
=1000+999*1000
=1000(999+1)
=1000000
(1988*9)*(1988*9)*(1988*9)的末位没有0
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