Properly resize Excel windows for laptop screen

I work with the same Excel spreadsheets on my iMac and my Mac laptops. When Yosemite came along suddenly the spreadsheet was too large to fit the laptop screen and the tabs at the bottom were not visible.

There are various complicated workarounds but finally here is a simple answer:

Just click Window in the top menu bar and select Zoom window. A real moment of triumph, that.

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