Well, try to find the difference. We have 5 terms from 16 to 24, and the difference is 8. so, each step must be increasing by 8/5. This gives the order:
23rd:1624th:168525th:168⋅2526th:168⋅35
We have a pattern, and that is that the answer for a given sequence is for any term n, we have 16+8∗(n−23)5. Try numbers out! And most importantly, plug 43 into that expression. What do you get?