Question

35×45×55×65×5算这种乘法有什么规律？

Answer 1

规律：乘数的个位均为5。
35*45*55*65*5
=5*7*5*9*5*11*5*13*5
=（5*5*5*5*5）*（7*11*13）*9
=3125*9*1001
=28125*（1000+1）
=28125000+28125
=28123125

Answer 2

35×45×55×65×5中都是5的倍数，可以先将5提取出来有
35×45×55×65×5
=(7x5) x (9x5) x (11x5) x (13x5) x (1x5)
=(7x9x11x13) x 5^5
=9009 x 3125
=(9000 + 9) x 3125
因为 ，9x3125 =（10-1)x 3125 =31250 - 3125 =28,125
9000x3125 = 28125000
(9000 + 9) x 3125 = 28125000 + 28125 = 28153125

Answer 3

35×45×55×65×5

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=1575×55×65×5

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=86625×65×5

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=5630625×5

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=28153

Answer 4

35×45×55×65×5=28153125