Where it says OR MORE for sisters in 4:176?
You continue to lie!
You missed
"earlier"
فَوْقَ ٱثْنَتَيْـنِ: It is a Possessive Phrase. First noun, Adverb of place, is in accusative case and relates to elided adjectival specification of preceding indefinite plural noun-women. It is functioning as adverb phrase in the sentence. Adverbs of place tell us where something happens. They are usually placed after the main verb or after the clause that they modify. Adverbs of place do not modify adjectives or other adverbs.
Thus the predicate: نِسَآءٙ فَوْقَ ٱثْنَتَيْـنِ means that if instead of the aforementioned case of two females in combination with a male, the offspring of you people have become three or more women (daughters)-----the apodosis clause will:
ثُلُثَا مَا: It is a Possessive Phrase. First noun is definite by construct with definite Relative Pronoun: مَا, in genitive case. dual in nominate case with its Noon dropped for construct. Originally it is: ثُلُثانِ, a fraction noun: nominator 2 of denominator 3 meaning two-thirds of some quantity. It is the subject of sentence.
تَرَكَ : This verbal sentence is the Linkage clause for preceding Relative Pronoun comprising of verb-hidden subject referent to deceased parent and object is elided being obviously understood: heritage. Thus the Subject part of the sentence means "the two-thirds of that (heritage) which he (the parent) has left". This is the simplest way of dividing the denominator-whole heritage into three equal parts; its two parts are allocated to offspring.
45. Therefore, despite the superb succinctness, it is clear that the allocation for females, weather, they are two or more, will be two-thirds of the heritage. A similar situation in respect of siblings is mentioned in Ayah 4:176 where the structuring of sentences is converse to that which are here in 4:11. A comparison will help perceive the meanings quite vividly:
اللہ تعالیٰ تم لوگوں(بنی نوع انسان) کو تمہاری اولاد کے مابین ترکے کی تقسیم کے متعلق وصیت/پابند کررہے ہیں اورہمیشہ کے لئے پابند کر دیا ہے؛بحثیت فرد اور معاشرہ:
لِلذَّكَرِ مِثْلُ حَظِّ ٱلۡأُنْثَيَيْـنِۚ
The equivalent of the allocation for the two female present in your progeny shall become the comparable measure - commensurate (مَثيلُ-مُمَاثِل) as privilege for the male in your genetic children.
تمہاری اولاد میں موجوددو مؤنث جنس رکھنے والی کے حصے میں آنے والی مقدار کے مماثل اولاد میں موجود مذکر جنس رکھنےوالے کا استحقاق مقرر کیا جاتا ہے(مؤنث،مذکر کے استعمال سے بن کہے اولاد میں مخنث شامل ہے)۔
فَإِن كُنَّ نِسَآءٙ فَوْقَ ٱثْنَتَيْـنِ فَلَـهُنَّ ثُلُثَا مَا تَرَكَۖ
Thereby, instead of a male co-sharer, if they (children) were womenfolk (three or more) who become above the place of two females referred to above, thereat, two-thirds of that which he (the deceased parent) has left, shall be the allocation for collective sharing by them (offspring).
اس اصول تقسیم کے پیش نطر اگر وہ(اولاد بجائے مذکر کی شمولیت کے)عورتوں پر مشتمل ہے جو بیان کردہ دو مؤنث سے اوپر کے مقام پر ہو جاتی ہیں تو بھی ان کے مابین تقسیم کےلئے اس ترکے کے دو تہائی پر استحقاق ہے جو مرحوم نے چھوڑا
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فَإِن كَانَتَا ٱثْنَتَيْـنِ فَلَهُمَا ٱلثُّلُثَانِ مِمَّا تَرَكَۚ
However, if there were two surviving Sisters, thereat, two-thirds of that which he (the deceased man who was all by himself) has left shall be allocated to them.
مگر اگر وہ سوگواران دو بہنیں ہیں/دو بھائی ہیں تو اس صورت میں ان کا استحقاق اس ترکے کا دو تہائی ہے جو مرحوم چھوڑ گیا ہے۔
وَإِن كَانُوٓا۟ إِخْوَةٙ رِّجَالٙا وَنِسَآءٙ فَلِلذَّكَرِ مِثْلُ حَظِّ ٱلۡأُنثَيَيْـنِۗ
And if they were siblings, comprising men and women, thereat, the two-thirds allocation shall be subdivided on the principle that equivalent of the amount accruing to the surviving two females shall be the sum allocated for the male.
اور اگر وہ سوگواران والد سگے بھائی بہن مردوں اور عورتوں پر مشتمل ہیں تو ان کے مابین دو تہائی ترکے کی تقسیم کا اصول یہ ہے:دو مؤنث جنس رکھنے والی موجود کے حصے میں آنے والی مقدار کے مماثل اولاد میں ایک مذکر جنس رکھنےوالے کا استحقاق مقرر کیا جاتا ہے
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I reiterate please devote sometime trying learning how to first understand the type of sentence by structure and meaning.
You have not mentioned from where you got "variable" phenomenon?
