Question

Express the given sets in roster form:

(ix) E = Set of natural numbers below 30 which are divisible by 2 or 5.

Answer 1

Step: Expressing set E in roster form

In roster form, the elements of the set are written inside a pair of curly braces and are separated by commas.

Given: E = Set of natural numbers below 30 which are divisible by 2 or 5.

Numbers divisible by 2 below 30 are 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, ,28, and 30.

Numbers divisible by 5 below 30 are 5, 10, 15, 20 and 25.

[Note: Common numbers should be taken only once while writing the set in roster form]

Hence, the roster form of set is
E = {2, 4, 5, 6, 8, 10, 12, 14, 15, 16, 18, 20, 22, 24, 25, 26, 28}.