Create a function that takes an array as an argument and returns true or false depending on whether the average of all elements in the array is a whole number or not.
is_avg_whole([1, 3]) ➞ true
is_avg_whole([1, 2, 3, 4]) ➞ false
is_avg_whole([1, 5, 6]) ➞ true
is_avg_whole([1, 1, 1]) ➞ true
is_avg_whole([9, 2, 2, 5]) ➞ falseN/A