Urgh, that was a shock. I needed to add a column of fractions, like this:

  • 1/4
  • 1/4
  • 1/10
  • 1/10
  • 1/25
  • 1/25
  • 1/25

I quickly realised I had not the faintest idea how to do it! Thank goodness for spreadsheets.

An online calculator then converted the sum to a decimal. Hooray!

Update, 17-Sep-2024: in mac OS 15.0 Apple Notes makes this a whole lot easier with Math Notes: type an expression followed by the equals (=) sign. Done!

Math Notes takes an equation, such as adding fractions and displays the result.