36/46 * 64/54
= 36/46 *(1+10/54)
=36/46+36/46 * 10/54
=36/46+(1-10/36)*10/54
=36/46+10/54-10/36 * 10/54
=36/46+10/54-100/(36*54)
=1-10/46+10/54-100/(36*54)
=1-20/486-25/486
=1-45/486
=1-5/54
=49/54
或者直接
36/46 * 64/54
=(1-10/36)*(1+10/54)
=1-10/46+10/54-100/(36*54）
=49/54