Except as provided in RCW 11.05A.060, if (1) it is not established by clear and convincing evidence that one of two co-owners with right of survivorship survived the other co-owner by one hundred twenty hours, one-half of the property passes as if one had survived by one hundred twenty hours and one-half as if the other had survived by one hundred twenty hours, and (2) there are more than two co-owners and it is not established by clear and convincing evidence that at least one of them survived the others by one hundred twenty hours, the property passes in the proportion that one bears to the whole number of co-owners.