# Números (2)

Números ordinales

 1o 1st first 2o 2nd second 3o 3rd third 4o 4th fourth 5o 5th fifth 6o 6th sixth 7o 7th seventh 8o 8th eighth 9o 9th ninth 10o 10th tenth 11o 11th eleventh 12o 12th twelfth 13o 13th thirteenth 14o 14th fourteenth 15o 15th fifteenth 16o 16th sixteenth 17o 17th seventeenth 18o 18th eighteenth 19o 19th nineteenth 20o 20th twentieth 21o 21st twenty-first 22o 22nd twenty-second 23o 23rd twenty-third 24o 24th twenty-fourth 30o 30th thirtieth 40o 40th fortieth 50o 50th fiftieth 60o 60th sixtieth 70o 70th seventieth 80o 80th eightieth 90o 90th ninetieth 100o 100th hundredth 1,000o 1,000th thousandth 1,000,000o 1,000,000th millionth

Los números ordinales se emplean:

– en títulos:

•  Queen Elizabeth II = (Queen Elizabeth the Second)
•  Pope John XXIII = (Pope John the Twenty-third)

– para referirse a siglos:

•  the 19th century = (the nineteenth century)

– para indicar la fecha:

•  April 3rd = (April the third)

Ver también las notas sobre La Fecha

Operaciones matemáticas

•  13 + 3 = 16 = thirteen plus three is sixteen= thirteen plus three equals sixteen= thirteen and three are sixteen
•  4 – 1 = 3 = four minus one is three
•  3 x 2 = 6 = three times two is six= three twos are six
•  20 ÷ 4 = 5 = twenty divided by four is five
•  a > b = a is greater than b
•  b < c = b is less than c