Question

find the cardinality of a set x=(x:x is a composite factor of 1020​

Answer 1

Given:

Set X such that, X = (X : X is a composite factor of 1020​)

To find:

Cardinality

Solution:

• We know that factors of 1020 = 1, 2, 3, 4, 5, 6, 10, 12, 15, 17, 20, 30, 34, 51, 60, 68, 85, 102, 170, 204, 255, 340, 510, 1020

• Composite numbers are the numbers that are divisible by more than just 1 and itself.

• Thus, the composite factor of 1020​ are = 4, 6, 10, 12, 15, 20, 30, 34, 51, 60, 68, 85, 102, 170, 204, 255, 340, 510, 1020

• Since the composite factors are 19 in total.

• Therefore, the cardinality of set X is 19.