• Question: why are there only 10 numbers

    Asked by whmichandbeale to Mike, Emma, Cees, Blanka, Anil on 2 Jul 2012.
    • Photo: Emma Trantham

      Emma Trantham answered on 2 Jul 2012:

      I think that this is because of the number system we work in. We work in decimal, or a 10 based number system. If we worked in binary there would only be two numbers: 1 and 0.

      I’m not sure who first came up with the decimal system but I think the ancient Egyptians used it.

      Maybe it became used so widely because we have 10 fingers so it made sense to use a system of 10 numbers? I don’t know. I wonder what the others think…

    • Photo: Blanka Sengerova

      Blanka Sengerova answered on 2 Jul 2012:

      I like the suggestion that we work in a decimanl system because we have only ten fingers, that never occurred to me, but makes total sense.

      As Emma says, the binary system only has 1s and 0s, which is what computers work with. I am quite fond of the hexadecimal system (base of 16) where the ‘numbers’ go 0,1,2,3,4,5,6,7,8,9,A,B,C,D,E,F – when I was little I found it fun to write words on my Dad’s calculator as it could write A-F. I know a bit geeky, but I remember it…

    • Photo: Michael Cook

      Michael Cook answered on 2 Jul 2012:

      We sometimes us Hexadecimal in Computing too!

      I think Emma nails the reason for why we have a decimal system. Binary is particularly handy for computers, though, because 1 and 0 can correspond to different electrical states (high and low voltages). It lets electrical circuits send signals along wires – very handy!