To solve this expression, we first need to simplify the terms within the parentheses.

5 5/28 can be converted to an improper fraction as:
5 * 28 + 5 = 140 + 5 = 145
So, 5 5/28 = 145/28

5 1/3 can be converted to an improper fraction as:
5 * 3 + 1 = 15 + 1 = 16
So, 5 1/3 = 16/3

Now, let's substitute these values back into the expression:
(145/28 - 16/3 * 1.25 - 1 16/21) divided by -1.5

= (145/28 - 16/3 * 1.25 - 19/7) / -1.5

Now, let's simplify further:
= (145/28 - 20 - 19/7) / -1.5
= (145/28 - 140/7 - 19/7) / -1.5
= (145/28 - 160/7) / -1.5
= (5/28) / -1.5
= 5/28 * -1/1.5
= -5/42

Therefore, the final answer is -5/42.