Question

State, giving reasons, which of the following pairs of sets disjoint sets and which are overlapping sets:
C = {Boys with ages above $20$ years} and D = {Boys with ages above $27$ years}

Answer 1

Disjoint sets: Two or more sets have no common elements.

Overlapping sets: Two or more sets have at least one common element.

Now, the given sets are,

C = {Boys with ages above $20$ years}

D={Boys with ages above $27$ years}

There are possibilities when the boys have age greater than $20$ years and also above $27$ years.

i.e., Who has more than $27$ years he must has more than $20$ years also.

Hence, the given sets are overlapping.