De or het optelling?

The correct Dutch article is:

de optelling

  • English: addition
  • Plural: de optellingen
  • Diminutive: het optellinkje
Rule Words ending in -ing: almost always de. See the rule
Meaning (Dutch) (wiskunde) het samenvoegen van een of meer termen tot een totaal, de som

How to use optelling

the additionde optelling
this additiondeze optelling
that additiondie optelling
our additiononze optelling
your additionjouw optelling
every additionelke optelling
which addition?welke optelling?
a big addition / the big additioneen grote optelling, de grote optelling
the addition (plural)de optellingen, deze optellingen

Dutch words ending in optelling

vectoroptelling

In compound words, the last part decides the article. See the rule

Meaning, plural, diminutive, pronunciation and translations: WikiWoordenboek (Dutch Wiktionary) (CC BY-SA 4.0). Example sentences: Tatoeba (CC BY 2.0 FR).