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... or OpenOffice.
You will find that the alternatives are almost equal.
No wonder: all Offices came from Xerox long ago .....
;JOOP!
 
I'd vote for Libra Office if you're looking for feature (or near feature) parity with Excel. If you want OSX/iOS/iCloud integration then I recommend Numbers. It has less features but is superior to Libra Office in the integration department.
 
If needing to view a spreadsheet is an occasional event you could always upload them to a Google Drive account for viewing in your browser. That way you wouldn't have to install anything.
 
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