Best Answer Tritonio , 16 September 2019 - 04:36 PM
Shift+= will not simply convert the number on screen to decimal representation. What it does is that it does the calculation on screen (in the last case Ans x 2) and shows the result of the calculation in decimal representation. So the first time you do Ans x 2 and you press =, the result gets stored in Ans. So when you then press Shift+= it will do the new Ans value, times two and show you that result in decimal.
Keep doing shift+= and you'll see that it keeps doubling it every time. The same thing that it would do if you kept pressing = after Ans x 2. It would keep doubling every time but it would show it as fraction.
Oh and to avoid it, use the S<->D button above the DEL button. This will convert the result from fraction to decimal and back to fraction (try pressing it many times) but it will do that without recalculating the expression you typed in.Go to the full post