Change the local variable to be called from global scope

Author: carlosyabreu

Sprint-2/1-key-errors/1.js

@@ -3,8 +3,15 @@
 // Why will an error occur when this program runs?
 // =============> write your prediction here
 
+// The code will throw a "SyntaxError: Identifier 'decimalNumber' has already been declared"
+// because the variable 'decimalNumber' is declared twice — once as a function parameter
+// and again with `const decimalNumber` inside the function.
+// Additionally, there will be a "ReferenceError: decimalNumber is not defined"
+// when trying to log it outside the function, since 'decimalNumber' only exists inside the function scope.
+
 // Try playing computer with the example to work out what is going on
 
+/**
 function convertToPercentage(decimalNumber) {
   const decimalNumber = 0.5;
   const percentage = `${decimalNumber * 100}%`;
@@ -13,8 +20,55 @@ function convertToPercentage(decimalNumber) {
 }
 
 console.log(decimalNumber);
+*/
+
+
+
+// Predict and explain first...
+
+// Why will an error occur when this program runs?
+// =============> write your prediction here
+// The code will throw a "SyntaxError: Identifier 'decimalNumber' has already been declared"
+// because the variable 'decimalNumber' is declared twice — once as a function parameter
+// and again with `const decimalNumber` inside the function.
+// Additionally, there will be a "ReferenceError: decimalNumber is not defined"
+// when trying to log it outside the function, since 'decimalNumber' only exists inside the function scope.
+
+// Try playing computer with the example to work out what is going on
+
+/** function convertToPercentage(decimalNumber) {
+	  const decimalNumber = 0.5;
+	  const percentage = `${decimalNumber * 100}%`;
+	  return percentage;
+    }
+
+    console.log(decimalNumber);
+*/
 
 // =============> write your explanation here
 
+// The first error happens because 'decimalNumber' is redeclared inside the function
+// even though it’s already defined as a parameter. JavaScript does not allow
+// redeclaring parameters with `let` or `const`.
+// The second error happens because 'decimalNumber' is not defined in the global scope
+// — it only exists inside the function, so `console.log(decimalNumber)` cannot find it.
+
 // Finally, correct the code to fix the problem
 // =============> write your new code here
+
+/**
+function convertToPercentage(decimalNumber) {
+  const percentage = `${decimalNumber * 100}%`;
+  return percentage;
+}
+
+console.log(convertToPercentage(0.5)); // Output: "50%"
+*/
+
+function convertToPercentage(decimalNumber) {
+  const percentage = `${decimalNumber * 100}%`;
+  return percentage;
+}
+
+console.log(convertToPercentage(0.5)); // Output: "50%"
+