What is the ruling for someone who has clean clothes mixed up with ritually impure ones, and how should they proceed to pray in them?

If pure garments become mixed with impure ones, the first opinion is to exercise diligence and effort in distinguishing the pure garment and praying in it, whether the number of garments is few or many.

As for the second opinion, one does not need to investigate; rather, there are two cases: 1. If the number of impure garments is known, the worshipper prays a number of times equal to the number of impure garments, plus one additional prayer, to ensure that he has prayed in a pure garment. 2. If the number of impure garments is not known, he prays in each garment until he is certain that he has prayed in a pure garment. This is similar to the case where the direction of the Qibla is uncertain, where one prays in all directions until certain of having prayed towards the Qibla.