The check digit is used to confirm the initial digits of the card number. The benefits of using a checksum is that it prevents casual attempts to invent credit card numbers, as only one in ten will be valid.
Length (adj). the longest, or longer, dimension of any object, in distinction from breadth or width; extent of anything from end to end; the longest line which can be drawn through a body, parallel to its sides; as, the length of a church, or of a ship; the length of a rope or line.
The length is the linear measurement of one side of the rectangle (usually the longest) and the width is the linear measurement of the other side of the rectangle (usually the â¦ shortest).In a square, both the length and the width would be the same.f 50 inches is the perimeter all you can say is that length plus width = 25 inches.