I'm in the planning phase of my next build. Mentally, I've got the spars on but there's no fresh sawdust on the floor yet.
Historically, when adding and subtracting fractions I have converted them to decimals and then plugged into a calculator. And then I would convert back to fractions. Which of course is dumb.
A week ago I found an iPhone app called Fraction Calculator Plus. I can't begin to explain how pleased I am with this app.
Here's a screenshot:
It's a big deal and is free.
Tony