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Erik and Ivy each writes down a fraction. They are surprised to find that the fractions they write are very similar: the denominator of each fraciton is exactly the same as the other\textquotesingle s numerator. What is the product of the two fractions? 
Overseas Competition->Knowledge Point->Calculation Modules->Fractions
Their fractions are just reciprocal of the other one. Thus, the product of the two fractions should be $1.$ 