docs: explain random integer generation formula

Author: gideondefar

Sprint-1/1-key-exercises/4-random.js

@@ -7,3 +7,16 @@ const num = Math.floor(Math.random() * (maximum - minimum + 1)) + minimum;
 // Try breaking down the expression and using documentation to explain what it means
 // It will help to think about the order in which expressions are evaluated
 // Try logging the value of num and running the program several times to build an idea of what the program is doing
+
+/*
+  What 'num' represents: A random whole integer between 1 and 100 inclusive.
+  
+  Order of evaluation breakdown:
+  1. (maximum - minimum + 1) // Calculates total size of target range (100).
+  2. Math.random()            //Generates a random decimal between 0 and 0.999...
+  3. Math.random() * 100      // Scales decimal up to a range between 0 and 99.999...
+  4. Math.floor(...)          // Rounds down to nearest integer, yielding 0 to 99.
+  5. + minimum                 //Shifts final range up by 1, resulting in 1 to 100.
+*/
+
+console.log(num);