1×2×3×4×5×6+·····+199×220的和是奇数还是偶数?
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1×2×3×4×5×6+·····+199×220的和是奇数还是偶数?
1×2×3×4×5×6+·····+199×220的和是奇数还是偶数?
1×2×3×4×5×6+·····+199×220的和是奇数还是偶数?
是偶数,因为不管前面的数相乘不管是奇数还是偶数,只要最后一个因数是偶数,积都是偶数,比如说:13×12=156,59×64=3776,981×532=521892,12×58=696,56648×18=1019664.结果都是偶数的.
偶数。任意几个数相乘,当存在至少一个偶数时则结果为偶数,因而6!、199*220皆为偶数。任意偶数相加结果为偶数,任意偶数个奇数相加,结果为偶数,省略号处为7+8+9+。。。+198,有96项奇数和96项偶数,则为偶数。三项偶数相加最终得偶数
偶数
1 2 3 4 ·····7 ·······10 ········?1 3 5 7 ·····?······?··········290 1 4 9 ·····?······?··········?
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