diff --git a/poincare/include/poincare/rational.h b/poincare/include/poincare/rational.h
index 9cf67a8ec..a79f485d0 100644
--- a/poincare/include/poincare/rational.h
+++ b/poincare/include/poincare/rational.h
@@ -39,8 +39,9 @@ public:
 private:
   ExpressionLayout * privateCreateLayout(FloatDisplayMode floatDisplayMode, ComplexFormat complexFormat) const override;
   int writeTextInBuffer(char * buffer, int bufferSize) const override;
-  Evaluation<float> * privateEvaluate(SinglePrecision p, Context& context, AngleUnit angleUnit) const override;
-  Evaluation<double> * privateEvaluate(DoublePrecision p, Context& context, AngleUnit angleUnit) const override;
+  Evaluation<float> * privateEvaluate(SinglePrecision p, Context& context, AngleUnit angleUnit) const override { return templatedEvaluate<float>(context, angleUnit); }
+  Evaluation<double> * privateEvaluate(DoublePrecision p, Context& context, AngleUnit angleUnit) const override { return templatedEvaluate<double>(context, angleUnit); }
+ template<typename U> Evaluation<U> * templatedEvaluate(Context& context, Expression::AngleUnit angleUnit) const;
 
   /* Sorting */
   int compareToSameTypeExpression(const Expression * e) const override;
diff --git a/poincare/src/rational.cpp b/poincare/src/rational.cpp
index f82acd23a..bddd42d3e 100644
--- a/poincare/src/rational.cpp
+++ b/poincare/src/rational.cpp
@@ -104,14 +104,10 @@ int Rational::compareToSameTypeExpression(const Expression * e) const {
   return i1.compareTo(&i2);
 }
 
-Evaluation<float> * Rational::privateEvaluate(SinglePrecision p, Context& context, AngleUnit angleUnit) const {
-  // TODO: implement when needed, use Integer.privateEvaluate
-  return new Complex<float>(Complex<float>::Float(NAN));
-}
-
-Evaluation<double> * Rational::privateEvaluate(DoublePrecision p, Context& context, AngleUnit angleUnit) const {
-  // TODO: implement when needed, use Integer.privateEvaluate
-  return new Complex<double>(Complex<double>::Float(NAN));
+template<typename T> Evaluation<T> * Rational::templatedEvaluate(Context& context, Expression::AngleUnit angleUnit) const {
+  T n = m_numerator.approximate<T>();
+  T d = m_denominator.approximate<T>();
+  return new Complex<T>(Complex<T>::Float(n/d));
 }
 
 ExpressionLayout * Rational::privateCreateLayout(FloatDisplayMode floatDisplayMode, ComplexFormat complexFormat) const {