What type of number cannot be written as a fraction p/q, where p and q are integers and q is not equal to zero?

The Irrational numbers

Step-by-step explanation:

The so called "irrational numbers" cannot be written as a fraction of the type p/q. These are for example the square root of numbers that are NOT perfect squares (i.e. , and many others.

Their particular name "Irrational Numbers" derives actually from the fact that they cannot be written as a "ratio" of two integer numbers.

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