I’ve been having a bit of difficulty in understanding the difference between them while I was reading maths textbooks in welsh and I’ve came across ‘nifer’ as in “Cyfrwch y niferoedd”. I’ve always thought it was supposed to be ‘rhifau’.
I appreciate any help!
In general (though there are grey areas!), it’s rhif / rhifau if you’re referring to actual numbers (digits/integers), and nifer / niferoedd if you mean ‘number’ as in ‘amount’.
Have a look at the Geiriadur yr Academi https://geiriaduracademi.org/ entry for ‘number’ - that gives you examples of various phrases/useages.
Mae nifer mawr o bobl yno
There are a large number of people there
there = yna/fan’na (in speech)
Thanks for the example Brynle!