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Joe writes an expression $\frac59\times\frac9{13}\times\frac{13}{17}\cdots $ Following the pattern, he writes middle fraction is \frac{45}{49}. What is the result of the expression? 
Overseas Competition->Knowledge Point->Calculation Modules->Fractions
The last fraction should be $\frac{85}{89}$, so the answer is $\frac5{89}.$ 