So helpful and timely as I was just learning this today! So basically my understanding is when it’s got “the” like “the four imams” I treat it like a noun-adjective but the gender of the number is opposite the gender of the singular noun. Both words are definite. But without the “the” like “four boys” it’s like an idaafah, so the second word is the noun and majroor. And the number is the first word and it’s gender is also the opposite of the singular noun. Both words indefinite. Is this correct?