Word
В этой пачке около пятидесяти скрепок, а не ста штук.
Meaning
In this pack there are about fifty paperclips, and not a hundred pieces.
Part of speech
sentence
Pronunciation
Course
Breakdown of В этой пачке около пятидесяти скрепок, а не ста штук.
не
not
а
and (contrastive)
этот
this [f: эта, n: это]
в
in / to (direction)
Questions & Answers about В этой пачке около пятидесяти скрепок, а не ста штук.
Why is "fifty" written as пятидесяти here?
The preposition около (around/about) requires the Genitive case. When declining compound numbers like пятьдесят, both halves of the word change. Both пять and десят decline like feminine nouns ending in a soft sign. So, пять becomes пяти, and десят becomes десяти, combining to make пятидесяти.
How does the number сто (one hundred) decline, and why is it ста in this sentence?
It is in the Genitive case because the preposition около still applies to the second part of the sentence ("about fifty... and not [about] a hundred"). The number сто has a very simple declension pattern: it is сто in the Nominative and Accusative cases, and changes to ста for all other cases (Genitive, Dative, Instrumental, and Prepositional).
Where does the о come from in скрепок? The dictionary form is скрепка.
Скрепок is the Genitive plural form, governed by the number 50. To form the Genitive plural of a feminine noun ending in -а, you drop the final vowel. That would leave the awkward consonant cluster "скрепк". To make pronunciation easier, Russian inserts a fleeting "fill vowel" (an о or an е) between the final consonants.
Why is the word added at the end?