# Are They Rational?

Number Theory Level 2

There exist three distinct rational numbers $$a$$, $$b$$, and $$c$$ such that $$\sqrt{a}+\sqrt{b}+\sqrt{c}$$ is also rational. At least how many of $$\sqrt{a}$$, $$\sqrt{b}$$, and $$\sqrt{c}$$ have to be rational?

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