Answer:
Change if(num < 20 && num > 30)
to
if(num < 20 || num > 30)
Explanation:
The code has lots of errors most of which are as a result of case sensitivity of java programming language
The following errors were corrected.
All System.Out.Println were changed to System.out.println
scan.NextInt() was changed to scan.nextInt()
Now to the actual correction that needs to be made;
The programmer's error was in using the conditional statement.
The programmer used if(num < 20 && num > 30) as its condition which means that if num is less tha 20 and at the same time greater than 30
This is impossible because no number is greater than 30 and less than 20 at the same time.
So, the correction made was to change the && (and) to || (or) which means that numbers greater than 30 or less than 20.
<em></em>
<em>This corrects the programmer's mistake</em>
<em>See attachment for complete code</em>