Is it permissible to purify some of the Wudu (ablution) organs together, such as the mouth and nose together?

The Sunnah regarding rinsing the mouth and nose is to combine them in one scoop of water and to do so three times, according to the Hadith of Uthman: "...then he put his hand in and rinsed his mouth and nose from a single scoop, doing that three times." And according to the Hadith of Ibn Hibban: "Three times from three scoops."