Question

Lester has to determine which of these square roots is rational.

A. √27
B. √55
C. √60
D. √81

Lester said that Choice C is correct because the number under a square root symbol needs to be even for the square root to be rational. What mistake did Lester make?

Answer 1

D

Step-by-step explanation:

Answer 2

Hi There!

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Lester's Mistake:

Just because a number is odd doesn't mean its not rational. For a square root to be a rational number it has to be a number that dosen't infinitely go on like choices A, B, and C.

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Correct Answer:

D. √81

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Step-by-step explanation:

Choice D is the only square root that doesn't have a infinite decimal because √81 equals 9.

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Hope This Helps :)