Calculator questions

Dymo

Just after getting a new casio scientific calculator and I'm trying to get the hang of it.

When I divide 0.015/12 I get the answer 1.25x10-3 where as what I want is 0.00125 which is the answer. What button do I have to press?

Thanks

anothernight

Shift + ENG should do it. You might have to do it twice though.

In my calculator doing that displays 0.00125x10^0, so just ignore the scientific notation bit.

wonderfulname

Its the same thing?

Dymo

anothernight wrote: »

Shift + ENG should do it. You might have to do it twice though.

In my calculator doing that displays 0.00125x10^0, so just ignore the scientific notation bit.

Thanks that worked but I had to do it twice and the notation bit at the end. Is there a away of just using it like a normal calculator for some functions

Its the same thing?

yes but more complicated when trying to use it in an equation.

bnt

What about SETUP -> NORM or SETUP -> FIX 4? That's how my FX-991ES works, and I think the FX-83 is the same?

PS: if it returns a fraction but you'd like a decimal representation, hit S<=>D.

LeixlipRed

I hate modern calculators. I just have a classic old casio one and I have no idea how to use the new ones. Students often look confused when you can explain all sorts of wonderous mathematical concepts yet you can't figure out how to change the yoke from degree to radian measure

MathsManiac

Firstly, the solution, (at, least I think this does it for most Casio calcs) -
If you have a SETUP or MODE menu, try to get to a menu offering you the options FIX-SCI-NORM. Press the option for NORM. If you then get a choice between 1 & 2, go for 2.

Anyway, OP, I think that to solve this problem and be able to solve it again if it happens in the future, it's useful to understand what's going on.

As far as most calculators are concerned, there are three standard ways to display numbers:
1. The "Normal" way, (sometimes called "floating point",)
2. "scientific notation", where you write it in the form a X 10^n, where a is between 1 and 10. (a is the "mantissa" and n is the "exponent")
3. "engineering notation", which is the same as scientific, except that the exponent is always a multiple of 3, and the mantissa can vary from 1 to 1000 instead of 1 to 10.

The rationale for engineering notation, by the way, is that the standard multiples and sub-multiples of base units go up in thousands: kilo- mega- giga- etc. So engineering notation allows you to write the answer easily in one of these units.

Anyway, calculators in general allow you to switch between the different notations. There's usually something in the setup that allows you to set the default way to display the number. There is often also a button labelled [FSE] that allows you to switch the number currently displayed between the different notations, without affecting the default mode ([FSE] is for "floating point", scientific", "engineering".)

The [ENG] button and [SHIFT][ENG] are related to engineering notation: they start hopping the exponent through multiples of 3, adjusting the mantissa accordingly, so as to allow you to switch units. Say your answer is in metres. If you're used to reading the display in this way, you can read 1.25 * 10^-3 as 1.25 mm. pressing [shift][eng] puts the mantissa into metres, doing it again puts it into kilometres, etc.

As a separate issue, there's also often a menu option called "FIX". This allows you to fix the number of decimal places displayed. For example, if you calculate 1/7, the answer usually displayed is 0.142857142. If you've done something like "FIX 4", that will display as 0.1429. (The calculator still stores and works with the full precision available to it; it's only the display that's getting rounded.) In the casio calculators, if you select scientific notation, you may then be asked to choose (from 1 to 9) the number of significant figures to display the mantissa. So, if you went for scientific [3], 1/7 would dislplay as 1.43*10^-1.

Finally, you may wonder what the choice between "normal 1" and "normal 2" mode is on the Casio calculators. "Normal 2" mode displays any number without using scientific notation if possible - if the number can fit on the display without using scientific notation, it does so, but if the number is too big or too small, it switches into scientific notation. "Normal 1" is similar as regards large numbers, but it switches automatically to scientific notation when the number drops below 0.01.

MathsManiac

LeixlipRed wrote: »

I hate modern calculators. I just have a classic old casio one and I have no idea how to use the new ones. Students often look confused when you can explain all sorts of wonderous mathematical concepts yet you can't figure out how to change the yoke from degree to radian measure

Bah, humbug, I hate these newfangled computer thingies. I like finding billion-digit primes with a pencil and paper (but only because my wax tablet kept melting when I sat too close to the fire).

LeixlipRed

Haha, no I'm not computer illiterate at all, I embrace technology but I dislike modern calculators. No help function readily available is the problem!

MathsManiac

I know - I just couldn't resist! I understand the point of view. The more features you get on a calculator, the more potential there is for something going wrong and you not knowing what, and the more complicated the menus become.

I've three or four different ones, and there's often a bit of headscratching when I switch from one to another.

LeixlipRed

Yeh, the different brands all seem determined to be just different enough from each other to confuse the casual user! Anyway, with the net so easily available while you're mobile these days I rarely ever use a calculator anymore.

Dymo

Wow thanks lads for the answers, the Norm 2 seems to have worked, Thank MathsManic for that helpful post