其它
If $a,b,c,d,e,f,g,h,j$ represents different digits from $1$ to $9$ such that $a+\frac{b}{c}+\frac{d}{e}\times f-\left(g+\frac{h}{j} \right) = N$, where $N$ is a whole number. What is the value of $\frac{d}{e}\times f$ to maximize $N$? 
Overseas Competition->Knowledge Point->Combinatorics->Combinatorics Involving Extreme Values->Forming a Maximum/Minimum Multi-Digit Numbers with Fixed Sums
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