Take the 2-minute tour ×
Mathematics Stack Exchange is a question and answer site for people studying math at any level and professionals in related fields. It's 100% free, no registration required.

Is it possible or not to calculate remainder through use of Casio fx-991 ES Calculator. If possible then how

for example :- I have to calculate remainder of 2345763534 rem 24 and other media except calculator is forbidden. If this isn't possible through calculator then any short cut method are also appreciated.

share|improve this question
4  
Divide 2345763534 by 24. Take the integer part of the quotient. Multiply by 24, and subtract that product from the original 2345763534. This difference is your remainder. –  oldrinb Apr 1 '13 at 2:38
1  
@oldrinb: we had the same idea. –  Thomas Apr 1 '13 at 2:40
    
@Thomas I hope :-) –  oldrinb Apr 1 '13 at 2:43
    
@oldrinb: Since your comment was a bit faster than my answer, you should add an answer :) –  Thomas Apr 1 '13 at 2:44
    
I don't know about my first question i.e whether it is possible in calculator directly or not... –  nKandel Apr 1 '13 at 10:48

4 Answers 4

up vote 5 down vote accepted

Use the calculator to find $$ 2345763534/ 24 = 97740147.25 $$ That is the remainder is $$ 2345763534 - 24\cdot 97740147 = \dots $$

share|improve this answer

I thought that I'd add the answer I found here as I found it more helpful than the current answer.

I am afraid that this calculator don't have any modulo function. However there is quite simple way how to count modulo using display mode ab/c (instead of traditional d/c).

How to switch display mode to ab/c:

  • go to settings (Shift + mode)
  • press arrow down (to view more settings)
  • select "ab/c" (number 1).

Then do your calculation (in comp mode), like 50 / 3 and you will see 16 2/3 thus mod is 2 or try 54 / 7 which is 7 5/7 (mod is 5). If you don't see any fraction then mod is 0 like 50 / 5 is 10.

The remainder fraction is shown in reduced form, so 60 / 8 will result in 7 1/2. Remainder is 1/2 which is 4/8 and mod is 4.

EDIT: Note that this doesn't work for everything. Especially if the fraction can be simplified (e.g. 6 mod 4). But I still believe it's a useful shortcut to keep in mind, just make sure the fraction has the modulus as the denominator.

share|improve this answer
1  
this doesn't work if d number is too large i.e on range of 10+ digit... anyway thanks for the answer –  nKandel Jun 1 '13 at 15:19

I know this is an old post, but you could do this on any calculator

5 % 4 = ? (5 mod 4)

5/4 = 1.25 to get the decimal form of the remainder subtract the number on left of decimal from result of 5/4

1.25 - 1 = .25 <-- the remainder .25 * 4 = 1 <-- remainder converted from decimal form

so...

5 mod 4 = 1

61 % 9 = ?

61/9 = 6.7777777777777777777777777777778

6.7777777777777777777777777777778 - 6

= 0.7777777777777777777777777777778

9 * 0.7777777777777777777777777777778 = 7

so 61 % 9 = 7

With this method, there might be cases where the multiplication at the end results in another decimal but this is due to rounding so just round up or down to the nearest whole number and that's your remainder

ie: on a cheap calculator with not so many decimal places

61 % 9 = ?

61/9 = 6.78

6.78 - 6 = 0.78

9 * 0.78 = 7.02

round 7.02 to whole # = 7

61 % 9 = 7

12 % 3 = ? 12/3 = 4.00 4.00 - 4 = 0 0 * 3 = 0 12 % 3 = 0

Note: This method doesn't work for negative integers

share|improve this answer
    
what if the starting number is so great that it doesn't fit the display of the calculator? –  mau Oct 9 '13 at 12:21
    
This is a manual method means you need to first divide then subtract and again multiply. This isn't method I would expecting at time of posting this question... Anyway thanks for answer. –  nKandel Oct 17 '13 at 5:40

I think jdeo's method works for negative integers aswell: -7 mod 4

-7/4=-1.75

Next step is make a positive fraction that is less than 1 -1.75+2=0.25

Then 0.25*4=1

Therefore -7 mod 4 = 1

Please do let me know if this is wrong :) Thanks

share|improve this answer

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.