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My calculator will only answer in fractions?

Just got a new CASIO fx-83GT PLUS calculator for chemistry this year, I like it except the fact that doing calculations like 3.12 x 10-3 (to the power of minus three) gives 39/ 12500 which isn't very useful?

I've tried the whole SHIFT --> MODE --> 2:LineIO thing and all it gives me is the fraction again, seperated by a comma (e.g 39,12500).

I've also tried the S<->D button (next to the M+ button) but it didn't seem to make any difference :confused:

This is really annoying me, the manual is confusing and everything people tell me to do isn't working? Surely you don't have to work with stupidly small numbers in fractions all the time? :frown:

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Why don't you just use fractions? Much more accurate...
Reply 2
Put it in Linear Mode? :rolleyes:
Reply 3
TheSownRose
Why don't you just use fractions? Much more accurate...


Most of the things I use the calculator for are for working out amounts of things, like how many moles of a substance, or molar mass etc. I can't put 39/12500 of a mole in an exam - or can I? :s-smilie:
Reply 4
Daniiel
Put it in Linear Mode? :rolleyes:


When I put it in Linear mode, it gave me the same answer, the same fraction, just seperated by a comma instead of a line :eek3:
Reply 5
have you tried just pressing shift or ctrl before you press the equals button? i have a ti-nspire but it works for me, and it did on my old casio scientific calculator as well
Reply 6
If it all else fails, just press the reset button then. :wink:
There is an sd button, that does it :smile:
Reply 8
That's weird..whenever I had that problem the S<->D button usually fixed it...How long have you had it? Maybe it's bust :/
Niki_girl
Just got a new CASIO fx-83GT PLUS calculator for chemistry this year, I like it except the fact that doing calculations like 3.12 x 10-3 (to the power of minus three) gives 39/ 12500 which isn't very useful?

I've tried the whole SHIFT --> MODE --> 2:LineIO thing and all it gives me is the fraction again, seperated by a comma (e.g 39,12500).

I've also tried the S<->D button (next to the M+ button) but it didn't seem to make any difference :confused:

This is really annoying me, the manual is confusing and everything people tell me to do isn't working? Surely you don't have to work with stupidly small numbers in fractions all the time? :frown:


I have that calculator. You do know that when it gives you a fraction as an answer the is a button you can press to convert the fractional answer into a numerical value??

I should also add that having it give an answer in fraction form by default can be useful (eg in maths/Phys etc you may be asked to specify an answer 'exactly' ie a surd or fraction rather than rounded decimal value), i vastly prefer it now that im used to it.

EDIT: upon closer inspection, i dont have that calculator but have one similar. The ability to change answer format ahould still be there though, i recommend studying the instruction manual for help re this issue
Reply 10
Or you can press the "Mode Setup" button and select the "STAT" option for a more permanent solution.
Reply 11
Reset it completely then try the S<>D button.
Reply 12
Or, alternatively, just press the fraction button (abca \frac{b}{c}) to switch the answer display back and forth between fractional and decimal values.
Reply 13
theths
have you tried just pressing shift or ctrl before you press the equals button? i have a ti-nspire but it works for me, and it did on my old casio scientific calculator as well


It didn't work, it just gave me back the sum I entered in a different format...
Reply 14
The SD button just gives me;

3.12 x 10-3

=

3.12 x -3/10

PS. The calculator is brand new, just started using it today, this is the first problem I've had with it :o:
Niki_girl
Most of the things I use the calculator for are for working out amounts of things, like how many moles of a substance, or molar mass etc. I can't put 39/12500 of a mole in an exam - or can I? :s-smilie:


I can't see why not - it's still the correct answer in fraction form.
Reply 16
bloomblaze
I have that calculator. You do know that when it gives you a fraction as an answer the is a button you can press to convert the fractional answer into a numerical value??

I should also add that having it give an answer in fraction form by default can be useful (eg in maths/Phys etc you may be asked to specify an answer 'exactly' ie a surd or fraction rather than rounded decimal value), i vastly prefer it now that im used to it.

EDIT: upon closer inspection, i dont have that calculator but have one similar. The ability to change answer format ahould still be there though, i recommend studying the instruction manual for help re this issue


Except I'm not doing maths or physics this year, just chemistry where the majority of maths is with standard form and very small numbers (for moles, particles etc.) and it's annoying me that by using a minus-power (e.g 10 to the minus 3) it has to give the answer as a fraction...

With 3.12 x 103 it gives 3120...so it's just the negative powers???
Reply 17
vinvan
Or you can press the "Mode Setup" button and select the "STAT" option for a more permanent solution.


Lol, which STAT option? This is the menu;

1: 1-VAR
2:A+BX
3:_+Cx2
4: 1n x
5:e^X
6: A . B^X
7:A. X^B
8:1/X
Niki_girl
Lol, which STAT option? This is the menu;

1: 1-VAR
2:A+BX
3:_+Cx2
4: 1n x
5:e^X
6: A . B^X
7:A. X^B
8:1/X


When you get to that screen, press AC or cancel or what ever. Then it should be fine. :woo:
Reply 19
When you press the s<=>d button does it do anything at all? Or does it swtich between 39/12500 and 3.12x10^-3, because 3.12x10^-3 is hardly difficult.. move the numbers 3 places to the right... And there's nothing wrong with leaving it in standard form. I believe theyd accept something like 0.0000000069 if you wrote it as 6.9x10^-9 which is what the calculator would give you... And they would probably prefer it in standard form too.

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