Russian Fractions

If you already know about cardinal and ordinal numbers, it is time to start using them together to say fractions in Russian. Fractional numbers are used to designate fractions. The basic examples of fractions in Russian are:

1/3 - одна третья [ahd-nah tryeht'-yah]
1/2 - одна вторая [ahd-nah ftah-rah-yah]
2/9 - две девятых [dvyeh dee-vyah-tikh]

As you might have noticed from the examples, the first part of a fractional numeral is the cardinal number, the second part is the ordinal number.

Agreement with nouns

The numbers in Russian follow the same grammar rules as adjectives. They must agree with nouns in gender (masculine, feminine, neuter), number (singular or plural) and case. You should use the feminine form of numerals 1 and 2 if they are located in the numerator, as in одна пятая (1/5). The noun after the fraction is always in the genitive, as in две третьих класса (two third of the class). As you can see from this example, the word класса is in the genitive form (the dictionary form is "класс").

In addition, Russian fractional numerals change by cases (i.e. decline). Both parts of the numeral must change. The first part (the numerator) is changed like the corresponding cardinal number. The second part (the denominator) is changed similar to the adjective интересный or синий. You may want to check out the lesson on declension of adjectives if you wish. The table below gives a few examples:

Case	Numeral две третьих (2/3)	Numeral две пятых (2/5)
Nominative	две третьих	две пятых
Genitive	двух третьих	двух пятых
Dative	двум третьим	двум пятым
Accusative	две третьих	две пятых
Instrumental	двумя третьими	двумя пятыми
Prepositional	(о) двух третьих	(о) двух пятых

Decimal fractions in Russian

Now look at the examples of decimal fractions. Notice that unlike in English, Russians use a comma (not a dot) to distinguish between the whole and the remainder.

0,5 - ноль целых, пять десятых
1,04 - одна целая, четыре сотых
2,75 - две целых, семьдесят пять сотых

Mastering Russian decimal fractions is a two-step process.

Say the number placed before the comma, followed by the word целая for numbers ending in 1, or the word целых for all other numbers.

For example: 0,.. - ноль целых; 3,.. - три целых; 41,.. - сорок одна целая
Then say the number after the comma followed by the word десятых (10th), сотых (100th), тысячных (1000th) depending on the type of a fraction.

For example: ..,5 - пять десятых; ..,41 - сорок одна сотая; ..,009 - девять тысячных

Shortcut names for some fractions

In spoken Russian, some fractions have special names:

1/2 is половина [pah-lah-vee-nah] (half)
1/3 is треть [tryeht'] (third)
1/4 is четверть [chyet-vyehrt'] (quarter)
1,5 is полтора [pahl-tah-rah] (one and a half)

The fraction половина declines like feminine nouns ending in -a (доска).

Declension of полови́на (a half)

Case	Singular	Plural
Nominative	полови́на	полови́ны
Genitive	полови́ны	полови́н
Dative	полови́не	полови́нам
Accusative	полови́ну	полови́ны
Instrumental	полови́ной (полови́ною)	полови́нами
Prepositional	полови́не	полови́нах

The fractions треть and четверть decline similar to feminine nouns ending in -ь (степь).

Declension of тре́ть (a third)

Case	Singular	Plural
Nominative	тре́ть	тре́ти
Genitive	тре́ти	трете́й
Dative	тре́ти	третя́м
Accusative	тре́ть	тре́ти
Instrumental	тре́тью	третя́ми
Prepositional	тре́ти	третя́х

Declension of че́тверть (a quarter)

Case	Singular	Plural
Nominative	че́тверть	че́тверти
Genitive	че́тверти	четверте́й
Dative	че́тверти	четвертя́м
Accusative	че́тверть	че́тверти
Instrumental	че́твертью	четвертя́ми
Prepositional	че́тверти	четвертя́х

The fractional numeral полтора declines as shown in the table below. Note that it has the form полутора in all cases except the nominative and accusative.

Declension of полтора
(stressed vowels are underlined)

Case	Numeral полтора галлона (a gallon and a half)
Nominative	полтора галлона
Genitive	полутора галлонов
Dative	полутора галлонам
Accusative	полтора галлона
Instrumental	полутора галлонами
Prepositional	(о) полутора галлонах

This concludes the lesson about Russian fractions. The following lessons will help you learn more about numerals and improve your understanding of the Russian grammar.

Related lessons

Got questions?

Ask them in the Russian Questions and Answers — a place for students, teachers and native Russian speakers to discuss Russian grammar, vocabulary, pronunciation, and other aspects of the Russian language.