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How to get answers in decimal on scientific calculator

I canu2019t speak to other engineering fields, but I personally have always use 3.14 in my calculations.

,That said, every engineer is familiar with the concept of tolerances in their particular field.

This means that a mechanical engineer is generally going to have far greater precision than a civil engineer designing a highway.

,So laying out a traffic circle they might round to just u201c3u201d but most software has a default value anyway (see my link at the bottom of the answer).

,It was pointed out scientific calculators have a pi key, so the issue is mostly moot anyway.

,In my case, I can order precision pins that we use in our tooling with 0.

0001u2033 tolerances.

We donu2019t use them often, but when needed they are available.

,Ironically, in many basic electrical calculation we can also use PI, and again 3.

14 seems to work when building circuits with 1% tolerance components (back in the 70u2032s most resistors were 10% and capacitors could vary even more).

,Too many decimal points and you are measuring with a micrometer and marking with a piece of chalk.

,I used this Dilbert before, but its still relevant to the answeru2026,By the way, given modern design software, this is pretty much moot except for mental u201cgut checku201d calculationsu2026,How is it that engineering coursework at universities so heavily uses calculusu2026 and yet only a small percentage of engineers seem to actually use calculus?3/12/21 Edit: I was playing with Python, and this little program demos the difference using the built-in function, as well as rounded version of Pi.

>>> degrees=45,>>> radians =degrees/360.

0*2*math.

pi,>>> math.

sin(radians),Using the math.

pi function, you get 0.

7071067811865475,If pi = 3.

1415, then 0.

7070904020014415,If pi = 3.

14, then 0.

706825181105366,if pi = 3.

0, the 0.

6816387600233341

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How to change a scientific calculator to normal mode

To put simply because the calculators were designed as such.Lets have some history.

First Casio calculators made before 1978 or so had no operator precedence.

They calculated everything left to right so 1+2*3 gave 9.

They also had no parenthesis so only way to change the order was to use the memory.

An example of such a calculator is the fx-29:,Then Casio introduced with Operator precedence.

Fx-39 was one of the first such calculators.

These also had parenthesis to change the order but they did not have the implicit multiplication so it is not directly relevant.

,In the 90s calculators where you entered the whole formula became common.

These included implicit multiplication.

They also included variables like x.

Now there was a question how to treat the implicit multiplication.

A simple solution is to treat like ordinary multiplication.

However, in math one often writes things like u201csin 2xu201d assuming it means u201csin(2x)u201d and not u201csin(2) * xu201d.

Therefore Casio chose in its W-series to give implicit multiplication higher precedence than normal multiplication and several other operators.

This was copied in the MS series that came in 2000.

In 2004 they introduced the ES series that had an all dot matrix display and had a math-io mode where one could enter formulas like on paper.

In addition it also had more traditional line-io mode.

They changed the way functions work so that when you pressed u201csinu201d you actually got u201csin(u201c.

This mandatory parenthesis removed ambiguities.

,They thought that because the ambiguity are solved one can reduce the priority of implicit multiplication to same as the normal one.

This makes things somewhat clearer to understand.

,For reasons I do not know this was an error and already in 2008 in the ES Plus series they went back to the implicit multiplication being in higher priority and it has remained so.

That means only in the 20 years of in line formula entry (30+ if one counts graphical calculators) the implicit multiplication has had same priority only for four years.

,I bought up the early ones to illustrate a point.

Was the fx-29 wrong as it did not do multiplications before divisions? Of course not, it was designed to do so.

A calculator is just a tool and it is for the user to know how to use it.

A calculator is not a magic box that gives you answers.

Modern calculators are so advanced that people forget this aspect.

Same is with other technology like cameras.

The order of operations a calculator uses is defined in the manual.

As long as the calculator follows that it works correctly.

One can have discussions which one is better.

Casio clearly has made the choice as it went back to implicit multiplication having higher precedence.

,When a user sees such a formula, he has to first understand what is meant with it, then he has to translate it to the language or keystrokes the calculator understands.

Sometimes this requires no change, sometimes he has to make changes depending on how his calculator works.

He cannot just blindly enter the formula and then blame the calculator.

,If a calculator treats implicit multiplication at higher precedence,it is will calculate 2*3=6 and then divide 6/6=1.

If it does not it first divides 6/2=3 and then multiplies 3*3=9.

,There is a reason why people typically use the line for division and not the division symbol.

I do not recall ever using it beyond the first four or so grades.

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how to change a decimal to a fraction on a calculator ti-84

Do you have a TI-84? If so, press the MODE key (2nd key, 2nd row).You will then see this screen, or a similar screen:,Scroll down to the row that starts ANSWERS: You might see two choices like you see here (u201cANSWERS:AUTO DECu201d, or you might see three choices (also including u201cFRACu201d).

,Use the arrows to highlight DEC then press ENTER then 2nd-Quit.

,You can also change an answer on a case-by-case basis.

When you got a fractional answer, press MATH then press [2] for the Decimal option.

,(or whatever the choice is on your calculator).