The most common and most likely answer to this crossword clue is the 10 letter word GRADUATION
I've seen this crossword clue in Financial Times
G
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More clues leading to the result GRADUATION
Buddy explains!
The straight part
We know that "leaving with 30/30" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case leaving with 30/30 = graduation.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does GRADUATION mean?
GRADUATION noun- The action or process of graduating and receiving a diploma for completing a course of study (such as from an educational institution).
- A commencement ceremony.
- A marking (e.g., on a container) indicating a measurement, usually one of many such markings that are each separated by a constant interval.
- The exposure of a liquid in large surfaces to the air, so as to hasten its evaporation.