Q. Is the following number rational or irrational?20Choose 1 answer:(A) Rational(B) Irrational
Evaluate square root of 20: Evaluate the square root of 20 to determine if it can be expressed as a fraction of two integers (which would make it rational).20=4×5=4×5=2×5
Determine rationality of 5: Determine if 5 is a rational or irrational number.Since 5 is a prime number, it does not have a perfect square root. Therefore, 5 cannot be expressed as a fraction of two integers.
Conclude rationality of 20: Conclude whether 20 is rational or irrational based on the previous step.Since 5 is irrational, and the product of a rational number (2) and an irrational number (5) is irrational, 20 is irrational.
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