Expressing fractions - general (numbers) : French language lesson

Beware not to mix up fractions (to describe a part of a whole: half, third, fourth...) and ordinal numbers (to describe an order/rank: 1st, 2nd, 3rd, 4th, ...).
For ordinal numbers, see Forming ordinal numbers (1st, 2nd, 10th...).

Look at these examples of fractions:

un cinquième
1/5 - one fifth

deux cinquièmes
2/5 - two fifths

seize vingtièmes
16/20 - sixteen twentieths

To express fractions in French, you usually use both cardinal (un/deux/trois...) and ordinal numbers (premier/cinquième...) the same way as in English (one fifth).

Note also that just like in English, the second number is plural if the first is.

ATTENTION:

Here are the irregular fractional numbers:

un demi
1/2

un tiers
1/3

deux tiers
2/3

trois quarts
3/4

un quart
1/4

Examples and resources

deux cinquièmes
2/5 - two fifths

un cinquième
1/5 - one fifth

seize vingtièmes
16/20 - sixteen twentieths

special forms

un demi
1/2

un quart
1/4

trois quarts
3/4

deux tiers
2/3

un tiers
1/3

Q&A

Gruff

Kwiziq language super star

14 April 2018

14/04/18

Hi William - I'm not quite sure I've understood what you're asking. Could you elaborate?

Bonnie

Kwiziq community member

4 July 2018

4/07/18

You'd hear this in a classroom, or maybe 'Trois sixièmes, ah! c'est une demie!' after some calculation.

Cécile

Kwiziq language super star

1 September 2018

1/09/18

Hi William,

I cannot think of a situation in every day life when you would use 'trois sixièmes' except in a Maths lesson...

Aurélie

Kwiziq language super star

22 December 2016

22/12/16

Bonjour Joakim ! The expression "le Tiers Monde" to say "the Third World" is fixed as it is in English: this is the only way to say this in French. "Le Troisième Monde" would feel like there are more than one world, i.e. one planet, when here it's more of a division of the world into three "parts", hence the use of the fraction here. À bientôt !