For this purpose, no. But otherwise yes, they are both used with other different meanings. In fact, this is the only case where they mean the same.
Ca can also be used as then, as you can see in my other comment. It can also be used to mean like: el este ca mine (he is like me), animale sălbatice ca urșii (wild animals like bears), rapid ca pantera (fast like the panther). It can also be used to mean as a: ca mamă... (as a mother...). And a few similar other scenarios among some expressions.
Decât has another meaning similar to doar or numai, that is to mean only, but must be used in a negation. So, while you would use doar like this: am doar un măr (I have only one apple), you would use decât as follows: nu am decât un măr (same meaning).
I beg to disagree. According to what I have heard, learnt and read, "ca" is used to make a comparison of equality, and "decât", of inequality.
Examples: Eu sunt mai înaltă decât ea. Era înaltă ca mine.
"I am taller than her. She is as tall as me"
As seen in the example above, the sentence "El are mai puține rațe ca bărbatul" fits the logic of the first example where the word "decât" is the one used.
Like the tips shows, ca is than, as or like:
- El e mai bun ca mine (he is better than me).
- El e ca mine (he is as/like me).
The other one, că is then or because:
- Am spus că nu pot veni (I said that I can't come).
- Îmi place că e bun (I like it cause it's good).
'fewer ducks', not 'less ducks'! Less milk, less butter. less sugar, less cat food. Fewer cars, fewer cats, fewer eggs, fewer bananas, fewer jokes, fewer mistakes.
i know right!! it marked me wrong for saying less not fewer! like seriously it basically the same!!!! :-(
Less is for uncountable things, like milk and butter; fewer is for countable things. You don't have "a single butter" or "multiple butters", so you can't have "fewer butter(s)".