The word(s) "sixth" appears 5 time(s) in 4 verse(s) in Quran in Muhammad Pickthal translation.

(1) Allah chargeth you concerning (the provision for) your children: to the male the equivalent of the portion of two females, and if there be women more than two, then theirs is two-thirds of the inheritance, and if there be one (only) then the half. And to each of his parents a sixth of the inheritance, if he have a son; and if he have no son and his parents are his heirs, then to his mother appertaineth the third; and if he have brethren, then to his mother appertaineth the sixth, after any legacy he may have bequeathed, or debt (hath been paid). Your parents and your children: Ye know not which of them is nearer unto you in usefulness. It is an injunction from Allah. Lo! Allah is Knower, Wise.

(2) And unto you belongeth a half of that which your wives leave, if they have no child; but if they have a child then unto you the fourth of that which they leave, after any legacy they may have bequeathed, or debt (they may have contracted, hath been paid). And unto them belongeth the fourth of that which ye leave if ye have no child, but if ye have a child then the eighth of that which ye leave, after any legacy ye may have bequeathed, or debt (ye may have contracted, hath been paid). And if a man or a woman have a distant heir (having left neither parent nor child), and he (or she) have a brother or a sister (only on the mother's side) then to each of them twain (the brother and the sister) the sixth, and if they be more than two, then they shall be sharers in the third, after any legacy that may have been bequeathed or debt (contracted) not injuring (the heirs by willing away more than a third of the heritage) hath been paid. A commandment from Allah. Allah is Knower, Indulgent.

(3) (Some) will say: They were three, their dog the fourth, and (some) say: Five, their dog the sixth, guessing at random; and (some) say: Seven, and their dog the eighth. Say (O Muhammad): My Lord is Best Aware of their number. None knoweth them save a few. So contend not concerning them except with an outward contending, and ask not any of them to pronounce concerning them.

(4) Hast thou not seen that Allah knoweth all that is in the heavens and all that is in the earth? There is no secret conference of three but He is their fourth, nor of five but He is their sixth, nor of less than that or more but He is with them wheresoever they may be; and afterward, on the Day of Resurrection, He will inform them of what they did. Lo! Allah is Knower of all things.