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CARDINAL NUMBER OF FINITE SET

**Cardinal Number of a Finite Set **

**It has been told that, the Cardinal number of
a finite set A is the number of distinct elements in the set A, and it is denoted
by n(A).**

**Example– 1)**

**a) A = { week of a year }**

** There are 52 weeks in
a year.**

** n(A) = 52 or the cardinal number of the set A = 52**

**Example-2)**

** If A = { x, y, z
} and
B = { p, q, r, s } then n(A) = 3
and n(B) = 4 **

** It is not possible to
define the cardinal number of an infinite set, the cardinal number of the empty
set φ is zero, as φ has no element, or n(φ) = 0, the cardinal number of a
Singleton set is 1. For example, if A = {
the present president of USA } then n(A) = 1.**