Odd Number/One-to-One Correspondence
ODD NUMBER An integer which is divisible by 2 with a remainder. Example: ??/??/??/?
ONE-TO-ONE CORRESPONDENCE A one -to-one matching relationship. If to every member in one set there corresponds one and only one member in a second set, and to every member in the second set there corresponds one and only member in the first set, the sets are said to be in one-to-one correspondence. Example: If every seat in a room is occupied by a person, and no person is standing, there is a one-to-one correspondence between the number of persons and the number of seats.