Suppose R = {1, 3, 5, 7, 9, 11, 13, 15, 17} and D = {3, 6, 9, 12, 15, 18, 21, 24, 27}. What is R ∩ D? A. {3, 9, 15} B. {1, 5, 7, 11, 13, 17} C. {1, 3, 5, 6, 7, 9, 11, 12, 13, 15, 17, 18, 21, 24, 27} D. {6, 12, 18, 21, 24, 27}

Mathematics · Middle School · Thu Feb 04 2021

Answered on

The correct answer is A. {3, 9, 15}.

The symbol "∩" represents the intersection of two sets, which consists of all the elements that are common to both sets. If we look at the sets R and D:

R = {1, 3, 5, 7, 9, 11, 13, 15, 17} D = {3, 6, 9, 12, 15, 18, 21, 24, 27}

The intersection of sets R and D, denoted R ∩ D, would include only the elements that are present in both R and D.

Comparing the elements of the two sets, the common elements are:

- 3 (which is both in R and D) - 9 (which is both in R and D) - 15 (which is both in R and D)

Therefore, R ∩ D = {3, 9, 15}.