Add prediction and explanation comments for cardNumber slicing issue

Author: moses77-boop

Sprint-2/2-mandatory-errors/3.js

@@ -7,3 +7,8 @@ const last4Digits = cardNumber.slice(-4);
 // Then run the code and see what error it gives.
 // Consider: Why does it give this error? Is this what I predicted? If not, what's different?
 // Then try updating the expression last4Digits is assigned to, in order to get the correct value
+
+
+//Solution 
+//Prediction - The code would not run because 'cardNumber' is declared as numbers instead of a string.
+//             The '.slice()' method belongs to strings and arrays, it could only work by treating it's subject as a sequence of characters.