Let’s look at the pattern:
Series: 789, 790, 780, 782, 772, 775, 765, ?
Split into alternating operations
We observe two interleaving patterns:
Odd positions:
789 → 780 → 772 → 765
Changes:
789 − 9 = 780
780 − 8 = 772
772 − 7 = 765
So pattern: −9, −8, −7, −6
Next odd term is:
765 − 6 = 759
Even positions (just for confirmation):
790 → 782 → 775
The next term continues the odd-position pattern.
Final Answer: 759