First, let's convert all the mixed numbers to improper fractions:
5 3/8 = 43/8
18 1/2 = 37/2
7 5/24 = 179/24
16 2/3 = 50/3

Now, we can simplify the expression:
(43/8 + 37/2 - 179/24) ÷ 50/3
(43/8 + 148/24 - 179/24) ÷ 50/3
(43/8 + (-31/24)) ÷ 50/3
(129/24 - 31/24) ÷ 50/3
98/24 ÷ 50/3
(98/24) (3/50)
(49/12) (3/50)
147/600

Therefore, the final result is 147/600 or 49/200.