[Conan the Librarian]

I thought it was an HP “Reverse Polish Notation” device, but, looking closer, I don’t see the “Enter” key.

My HP-11c that I bought in 1985 still works great!

[editor-surveyor]

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Look closely and you’ll see the = key.

My wife has an 11c and a recent 12c. I have several 41cx and 15c’s

You have to use lots of scratch pads to use anything else!
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