車棚里自行車和三輪車,輪子數(shù)和車子數(shù)都是奇數(shù),你知道自行車和三輪車數(shù)量是奇數(shù)還是偶數(shù)

數(shù)學(xué)人氣：808 ℃時間：2019-11-01 09:11:49

優(yōu)質(zhì)解答

因為,自行車的輪子數(shù)是偶數(shù),偶數(shù)×奇數(shù) = 偶數(shù),偶數(shù)×偶數(shù) = 偶數(shù),
所以,自行車的輪子總數(shù)必然是偶數(shù)；
已知,兩種車的輪子總數(shù)是奇數(shù),奇數(shù)-偶數(shù) = 奇數(shù),
可得：三輪車的輪子總數(shù)是奇數(shù)；
因為,三輪車的輪子數(shù)是奇數(shù),奇數(shù)×奇數(shù) = 奇數(shù),奇數(shù)×偶數(shù) = 偶數(shù),
所以,三輪車數(shù)量必然是奇數(shù)；
已知,兩種車的總數(shù)是奇數(shù),奇數(shù)-奇數(shù) = 偶數(shù),
可得：自行車數(shù)量是偶數(shù).