Ask HN: Why don't calculators have an "into" button? Or do they?

1 points by gushogg-blake 1y ago ↗ HN

Multiplication is the same both ways so it doesn't matter, but for division I'm always wanting a button that says (last result) "into" x. Basically division with the two sides swapped.

Instead you have to type x, divide button, then type out the last result. Am I missing something?

3 comments

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colinb 1y ago ↗

Does your calculator have a reciprocal button? That’d get you to the desired result with only one extra keystroke.

gushogg-blake 1y ago ↗

I was wondering if that was a thing but no. It does have a little panel for more advanced operations and a toggle to invert them (roots, logs, exponents etc) but seemingly no reciprocal.

PaulHoule 1y ago ↗

I used to use one of these

https://en.wikipedia.org/wiki/HP_48_series

where you kept values on the stack and could reverse the values with the SWAP key. I currently have a

https://en.wikipedia.org/wiki/HP_Prime

which I use in Algebraic mode instead of RPN.