I did NOT have this problem with the previous version!
This appears to be a bug, as the view scale is held when set to 75%, but not when set to 100%. Tell Apple directly, using Provide Numbers Feedback, found in the Numbers menu. Classify it as a bug report, and include Numbers 3.0 in your subject line.
I wasn't sure if I had explained my issue properly - but you understood. Thank you and I will! Have a great day :)
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