The Cardinal number
El cardinal indica el número o cantidad de elementos de un conjunto, sea esta cantidad finita o infinita. Los números cardinales constituyen una generalización interesante del concepto de número natural, permitiendo comparar la cantidad de elementos de conjuntos infinitos.A continuacion se les presenta "the Ordinal numbers" y "the Cardinal Numbers" con la finalidad de que puedan diferenciarlos:
Table of Cardinal Numbers
1 | one | 11 | eleven | 21 | twenty-one | 31 | thirty-one |
2 | two | 12 | twelve | 22 | twenty-two | 40 | forty |
3 | three | 13 | thirteen | 23 | twenty-three | 50 | fifty |
4 | four | 14 | fourteen | 24 | twenty-four | 60 | sixty |
5 | five | 15 | fifteen | 25 | twenty-five | 70 | seventy |
6 | six | 16 | sixteen | 26 | twenty-six | 80 | eighty |
7 | seven | 17 | seventeen | 27 | twenty-seven | 90 | ninety |
8 | eight | 18 | eighteen | 28 | twenty-eight | 100 | a/one hundred |
9 | nine | 19 | nineteen | 29 | twenty-nine | 1,000 | a/one thousand |
10 | ten | 20 | twenty | 30 | thirty | 1,000,000 | a/one million |
Separation between hundreds and tens
Hundreds and tens are usually separated by 'and' (in American English 'and' is not necessary).
110 - one hundred and ten
1,250 - one thousand, two hundred and fifty
2,001 - two thousand and one
Hundreds
Use 100 always with 'a' or 'one'.
100 - a hundred / one hundred
'a' can only stand at the beginning of a number.
100 - a hundred / one hundred
2,100 - two thousand, one hundred
Thousands and Millions
Use 1,000 and 1,000,000 always with 'a' or 'one'.
1,000 - a thousand / one thousand
201,000 - two hundred and one thousand
Use commas as a separator.
57,458,302
The Number 1,000,000,000
In English this number is a billion. This is very tricky for nations where 'a billion' has 12 zeros. 1,000,000,000,000 in English, however, is a trillion.
But don't worry, these numbers are even a bit problematic for native speakers: for a long time the British 'billion' had 12 zeros (a number with 9 zeros was called 'a thousand million'). Now, however, also in British English 'a billion' has 9 zeros. But from time to time this number still causes confusion (just like this paragraph, I'm afraid). ;o)
Singular or Plural?
Numbers are usually written in singular.
two hundred Euros
several thousand light years
The plural is only used with dozen, hundred, thousand, million, billion, if they are not modified by another number or expression (e.g. a few / several).
hundreds of Euros
thousands of light year.