5.78778778 ….. is an irrational number because the decimal can't be represented as a ratio or fraction.
<h3>What are irrational numbers?</h3>
Irrational numbers are the set of real numbers that cannot be expressed in the form of a fraction, x/y where x and y are integers.
In other words, an Irrational Number is a real number that cannot be written as a simple fraction.
For example π = 3.1459....
π cannot be written as a fraction or ratio.
The decimals of irrational number goes on forever without repeating.
The decimals are continuous.
Therefore, 5.78778778 ….. is an irrational number because the decimal can't be represented as a ratio or fraction.
learn more on irrational number here: brainly.com/question/3386568
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