In this test - https://practicereasoningtests.com/practice-numerical-test - question 2, I'm surprised by the answer: IT and the explanation:

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**IT total Supervisor base and bonus = £52940 plus £4500 = £57440 with IT Support Staff £16000 plus £800 = £16800. Differential between £57440 and £16800 is £40,640 which highlights the largest difference across all functions. Therefore, "IT" is correct.**[/FONT]

I would expect the answer to be: Finance.

Can anyone give me a clearer explanation?

Ed.