Document how Math.random expression generates a number between 1 and 100

Author: fromonda

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

@@ -3,7 +3,12 @@ const maximum = 100;
 
 const num = Math.floor(Math.random() * (maximum - minimum + 1)) + minimum;
 
-// In this exercise, you will need to work out what num represents?
+// In this exercise, you will need to work out what num represents
 // 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
+
+// Math.random() gives a random decimal number between 0 and 1
+// Math.random() * (maximum - minimum + 1) gives a random decimal number between 0 and 100
+// Math.floor() removes the decimal part, giving a whole number between 0 and 99
+// + minimum shifts the range up so the final result is between 1 and 100