Predict and explain errors. Fix by removing line and making variable outside function

Author: MahirShah300

Sprint-3/1-key-errors/1.js

@@ -2,19 +2,41 @@
 
 // Why will an error occur when this program runs?
 // =============> write your prediction here
+//decimalNumber already exists as a parameter, so const decimalNumber is making
+//a new variable with the same name. There is also a problem where decimalNumber is being
+//assigned 0.5, which won't cause errors, but means that no matter what is passed to the function
+//decimalNumber will always be 0.5
 
 // Try playing computer with the example to work out what is going on
 
-function convertToPercentage(decimalNumber) {
-  const decimalNumber = 0.5;
-  const percentage = `${decimalNumber * 100}%`;
+//function convertToPercentage(decimalNumber) {
+//  const percentage = `${decimalNumber * 100}%`;
 
-  return percentage;
-}
+//  return percentage;
+//}
 
-console.log(decimalNumber);
+//convertToPercentage(0.6)
+//console.log(decimalNumber);
 
 // =============> write your explanation here
+//SyntaxError: Identifier 'decimalNumber' has already been declared
+//prediction correct, decimalNumber already exists so causes error. Removing the line
+//shows another error
+//console.log(decimalNumber);
+//            ^
+//ReferenceError: decimalNumber is not defined
+//This is because of scope, decimalNumber is defined in the function, so it only has scope
+//in the function
 
 // Finally, correct the code to fix the problem
 // =============> write your new code here
+
+function convertToPercentage(decimalNumber) {
+  const percentage = `${decimalNumber * 100}%`;
+
+  return percentage;
+}
+
+let decimalNumber = 0.6;
+console.log(decimalNumber);
+console.log(convertToPercentage(decimalNumber));