Which of the following sets are finite and which are infinite?

(i) Set of concentric circles in a plane.


(ii) Set of letters of the English Alphabets.


(iii) {x N : x > 5}


(iv) {x N : x < 200}


(v) {x Z: x < 5}


(vi) {x R:0 < x < 1}.

(i) In a plane there can be infinite concentric circles. Hence it is an infinite set.


(ii) There are just 26 letters in English Alphabets and are finite. Hence it is finite set.


(iii) It is an infinite set because, natural numbers greater than 5 is infinite.


(iv) It is a finite set. Natural numbers start from 1 and there are 199 numbers less than 200. Hence it is finite.


(v) It is an infinite set. Because integers less than 5 are infinite.


(vi) It is an infinite set. Because between two real numbers, there are infinite real numbers.


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