Crossword Genius

Calculate maximum that trade union will accept? On the contrary (3,2)

Ross

I believe the answer is:

tot up

I'm a little stuck... Click here to teach me more about this clue!

'calculate' is the definition.

'maximum that trade union will accept? on the contrary' is the wordplay.
I cannot really see how this works, but
'union' could be 'tu' (abbreviation for trade union) and 'tu' is found in the answer.
'maximum' could be 'top' (similar in meaning) and 'top' is found in the remaining letters.
This accounts for all the letters.
This may be the basis of the clue (or it may be nonsense).

Can you help me to learn more?

(Other definitions for tot up that I've seen before include "Summate" , "Count" , "Determine the sum of" , "Do summer job" , "Add together (driving offences)" .)

I've seen this clue in The Independent.
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