Added function(isProperFraction)

Author: ahmadehsas

Sprint-3/2-mandatory-rewrite/2-is-proper-fraction.js

@@ -1,6 +1,7 @@
 function isProperFraction(numerator, denominator) {
-    if (numerator < denominator) return true;
-    // add your completed function from key-implement here
+  if (Math.abs(numerator) < Math.abs(denominator)) return true; // This version of code works correctly for proper and negative fractions.
+  if (Math.abs(numerator) >= Math.abs(denominator)) return false;
+  if (Math.abs(numerator) === Math.abs(denominator)) return false;
 }
 
-module.exports = isProperFraction;
+module.exports = isProperFraction;