This is a math problem. To solve this we create a ratio of the radius of Pluto to the Moon.

showing that Pluto is about 68% the size of the moon. You asked if Pluto was less than

or 66%, or less the size of the moon.
68>66 so the answer is
False if you are talking about the volume or size of the two.
If you are talking about density, the ratio would be:

which equals 56% so the answer would be
True if you are inquiring about density.
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