"The keyboards of the computers are dirty."
Translation:Tastaturile calculatoarelor sunt murdare.
No, it is not.
The word "calculator" has several meanings and declensions. For some meanings it is considered a masculine noun, while for others it is considered a neuter noun. In the above sentence, the word refers to the computing device, which is always a neuter noun in Romanian.
On the Dexonline results page for "calculator" (link) you can see that, for each dictionary source, there are several meanings listed, each one preceded by something like "sn" or "sm", which correspond to neuter noun and masculine noun, respectively. The meaning we are interested in is preceded by "sn" on that page. Now, if you click on the declensions tab (link), you will see only the declension table for the masculine variant, even though the text in blue mentions that the word has two declension tables. This is an omission on the Dexonline page. As an alternative, you can check out the declension table for the neuter variant on Wiktionary (link).