Question

The set O represents the maximum temperatures, in degrees Fahrenheit, recorded in the city of Orlando in a year.

O = {71, 71, 72, 73, 77, 77, 79, 83, 84, 89, 90, 91}

The set T represents the maximum temperatures, in degrees Fahrenheit, recorded in the city of Tampa in a year.

T = {70, 72, 76, 78, 81, 81, 84, 86, 86, 89, 90, 90}

How many elements are in the set O ∪ T?

Answer 1

http://en.wikipedia.org/wiki/Union_(set_theory)

Answer 2

common and not common elements written once