How do you perform operations in base 13?

[neonerd]

I understand that 6x9 in base 13 = 42, but how do you actually perform the operation?

how about for 3x4?

 

[chuckywang]

6*9 = 54 base 10 = 42 base 13
3*4 = 12 base 10 = C base 13

 

[daveshel]

Use a deck of playing cards.

 

[Jzero]

I only know how to do it by converting the base-10 product to base-N

 

[Pepsi90919]

with a calculator

 

[Ophir]

54 in base 10 = 5*10^1+4*10^0
54 in base 13 = 4*13^1+2*10^0

 

[neonerd]

Originally posted by: Ophir
54 in base 10 = 5*10^1+4*10^0
54 in base 13 = 4*13^1+2*10^0

why do you randomely add 2 though?
and why is it that 6*9 become 4*13? and then you add that random 2

 

[TuxDave]

Are you asking how to operate natively in base 13 or how to convert it back and forth from base 13 to base 10?

 

[neonerd]

Originally posted by: TuxDave
Are you asking how to operate natively in base 13 or how to convert it back and forth from base 13 to base 10?

how to operate natively in base 13

 

[dighn]

to do it in base 13 directly you'd have to memorize a new multiplication table or do it the long way (adding 6 9 times or vice versa) but you can "cheat", do it in base 10 and then convert

 

[TuxDave]

Originally posted by: dighn
to do it in base 13 directly you'd have to memorize a new multiplication table or do it the long way (adding 6 9 times or vice versa) but you can "cheat", do it in base 10 and then convert

Said it before I could. For single digit multiplication in base 13, you either convert it to base 10 and do it, then convert it to base 13 afterwards OR relearn your multiplication table.

If you can get single digit multiplication memorized, then you're good to do multi-digit multiplication without memorization.

 

[chuckywang]

Originally posted by: neonerd

Originally posted by: Ophir
54 in base 10 = 5*10^1+4*10^0
54 in base 13 = 4*13^1+2*10^0

why do you randomely add 2 though?
and why is it that 6*9 become 4*13? and then you add that random 2

Don't confuse him.

54 in base 10 = 42 in base 13.

54 in base 13 = 5*13^1+4*13^0 = 69 in base 10.

 

[desteffy]

Originally posted by: neonerd
I understand that 6x9 in base 13 = 42, but how do you actually perform the operation?

how about for 3x4?

hahaha he said 42

how unexpected

 

[neonerd]

Originally posted by: chuckywang

Originally posted by: neonerd

Originally posted by: Ophir
54 in base 10 = 5*10^1+4*10^0
54 in base 13 = 4*13^1+2*10^0

why do you randomely add 2 though?
and why is it that 6*9 become 4*13? and then you add that random 2

Don't confuse him.

54 in base 10 = 42 in base 13.

54 in base 13 = 5*13^1+4*13^0 = 69 in base 10.

so where did you get the 5 now to multiply? also, why'd you add 4 now instead of 2?

 

[Jzero]

Originally posted by: neonerd

so where did you get the 5 now to multiply? also, why'd you add 4 now instead of 2?

Here's how it goes.
In base 10, 6x9 = 54, which is the same as (5x10^1) + (4x10^0).
To convert to base N, you have to do some division to figure out how many of each N go into each base-10 digit.

First, divide 54/13 to get the 13^1 column. You get 4 for that column.
4x13 = 52, so your remainder is 2 in the 13^0 column.

That gives you 42 in base 13.

Now try and covert 79 to base 13.
You should get 61.

 

[nakedfrog]

I assume you're not familiar with working with the hexadecimal system? It's basically the same deal, except base 13 instead of 16.

 

[Colt45]

same as hex but not.

once it gets to 12, she rolls over (= 10)
but its not "10" its 13. eetc.

 

[EarthwormJim]

Why do computer nerds always confuse Christmas and Holloween?

 

[mobobuff]

I don't know about all that, but I do know that your Syringer thread got BITCHSLAPPED!

 

[neonerd]

Originally posted by: Jzero

Originally posted by: neonerd

so where did you get the 5 now to multiply? also, why'd you add 4 now instead of 2?

Here's how it goes.
In base 10, 6x9 = 54, which is the same as (5x10^1) + (4x10^0).
To convert to base N, you have to do some division to figure out how many of each N go into each base-10 digit.

First, divide 54/13 to get the 13^1 column. You get 4 for that column.
4x13 = 52, so your remainder is 2 in the 13^0 column.

That gives you 42 in base 13.

Now try and covert 79 to base 13.
You should get 61.

oooo, i get it now
thanks

 

[neonerd]

Originally posted by: mobobuff
I don't know about all that, but I do know that your Syringer thread got BITCHSLAPPED!

haha, i got confused at first....was my thread *gasp* deleted??

 

[BigJ]

Originally posted by: EarthwormJim
Why do computer nerds always confuse Christmas and Holloween?

Because Dec 25 is Oct 31!!one!11!!

 

[TheLonelyPhoenix]

Originally posted by: EarthwormJim
Why do computer nerds always confuse Christmas and Holloween?

Oct 31 == Dec 25

Come on, any self-respecting geek should know that one.

 

[sharkeeper]

ALL YOU BASE ARE BELONG TO US

 

[Syringer]