This may have been intentional, but I noted a gotcha in this line:     $num=int(rand $#arr); That will never pick the last index in @arr (as long as there is more than one element in @arr); 10 * 10 will always be the last question asked.

A quick example: With four elements in @arr, $#arr is 3. rand(3) will return a number >= 0 and < 3. When you truncate the result with int(), you get 0, 1, or 2.

I would have written that line as:     $num=int(rand @arr);