Números Ordinais em ingles

1st – first
2nd – second
3rd – third
4th – fourth
5th – fifth (A letra “f” no meio some, basta dizer /fith/. Cf. Vocabulário: “Pentacampeão”)
6th – sixth
7th – seventh
8th – eighth
9th – ninth
10th – tenth
11th – eleventh
12th – twelfth (Cf. Ortografia: Décimo-segundo)
13th – thirteenth
14th – fourteenth
15th – fifteenth
16th – sixteenth
17th – seventeenth
18th – eighteenth
19th – nineteenth
20th – twentieth
21st – twenty-first
22nd – twenty-second
23rd – twenty-third
24th – twenty-fourth
25th – twenty-fifth
26th – twenty-sixth
27th – twenty-seventh
28th – twenty-eighth
29th – twenty-ninth
30th – thirtieth
40th – fortieth (Cf. Ortografia: FORTY)
50th – fiftieth
60th – sixtieth
70th – seventieth
80th – eightieth
90th – ninetieth
100th – one hundredth
1,000th – one thousandth
1,000,000th – one millionth
1,000,000,000th – one billionth (Cf. Falsos Cognatos: BILLION)

FONTE: http://www.teclasap.com.br/blog/2009/10/19/os-numeros-ordinais-em-ingles/