數學問題 答案不只一種

abcd/efghiabcdefghi各為1~9的數字且各數字都只能用一次請給我答案 abcd/efghi 要等於 1/2 or 1/3 or ....... or 1/9好像蠻難解釋的我舉例好了像 7329/14658=1/2給我越多答案越好謝謝喔!可以告訴我有特別的解法嗎?
全部有 89 個如果不限制分母為 1 位數還有 100 左右(電腦跑的)6789/54312 = 1/85789/46312 = 1/84689/37512 = 1/88439/67512 = 1/86839/54712 = 1/84589/36712 = 1/85839/46712 = 1/87364/58912 = 1/88179/65432 = 1/88954/71632 = 1/85976/41832 = 1/76479/51832 = 1/87894/63152 = 1/88394/67152 = 1/84769/38152 = 1/88419/67352 = 1/85697/34182 = 1/68174/65392 = 1/88953/71624 = 1/87956/31824 = 1/49267/18534 = 1/29327/18654 = 1/26927/13854 = 1/29158/73264 = 1/87932/15864 = 1/25796/23184 = 1/49523/76184 = 1/87692/15384 = 1/26792/13584 = 1/27123/56984 = 1/89723/48615 = 1/59627/48135 = 1/52967/14835 = 1/57629/38145 = 1/53729/18645 = 1/52769/13845 = 1/52973/14865 = 1/59237/46185 = 1/56297/31485 = 1/52697/13485 = 1/53297/16485 = 1/52937/14685 = 1/59352/74816 = 1/85418/37926 = 1/75892/47136 = 1/88942/71536 = 1/89273/18546 = 1/27923/15846 = 1/28932/71456 = 1/89182/73456 = 1/87293/14586 = 1/23187/25496 = 1/85832/17496 = 1/37312/58496 = 1/85237/41896 = 1/85274/36918 = 1/74653/27918 = 1/66791/54328 = 1/89416/75328 = 1/85791/46328 = 1/89541/76328 = 1/85916/47328 = 1/87416/59328 = 1/87941/63528 = 1/89316/74528 = 1/84691/37528 = 1/84591/36728 = 1/86741/53928 = 1/87269/14538 = 1/29156/73248 = 1/89531/76248 = 1/86729/13458 = 1/27329/14658 = 1/22943/17658 = 1/62394/16758 = 1/79421/75368 = 1/85921/47368 = 1/87421/59368 = 1/89321/74568 = 1/84392/17568 = 1/43942/15768 = 1/45371/42968 = 1/87614/53298 = 1/76381/57429 = 1/96471/58239 = 1/98361/75249 = 1/92637/18459 = 1/75823/17469 = 1/34527/31689 = 1/7如果有問題

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