The set A defined as a multiple of 3 that are less than 20 is given as:
A = {3,6,9,12,15,18}
A set is a collection of elements in a defined order
The universal set U which contains natural number of at most 25 is given as
U = {1,2,3,4,5,6,7,8,9,10,...,25}
The set A defined as a multiple of 3 that are less than 20 is given as
A = {3,6,9,12,15,18}
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