Question

What is the set that represents the universal set?

• A. {12, 14, 15, 18, 21}
• B. {10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21}
• C. {10, 11, 12, 14, 15, 18, 21}
• D. {21}

Answer 1

The correct option is B {10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21}

Universal set consists of all elements of set A, set B and all other elements. Here,
set A = {14, 21}
set B = {12, 15, 18, 21}
other elements = { 10, 11, 13, 16, 17, 19, 20}
Hence, the universal set is {10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21}.