Answer: Choice B
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Step-by-step explanation:
Using your calculator, you should find that
- sqrt(125) = 11.1803 approximately
- sqrt(196) = 14 exactly
- sqrt(207) = 14.387 approximately
- sqrt(220) = 14.832 approximately
Each approximate result has its decimal digits go on forever without any pattern. So we cannot write those values as a fraction of two integers. The decimal expansion must have some kind of pattern that repeats forever, so we could consider it rational.
Only choice B results in a whole number. The value 14 is the same as 14/1, showing it can be written as a fraction of two integers. Therefore choice B is rational.