Answer:
... 0.7 . . . or 0.67 . . . or 0.667 . . . or 0.6667 . . . or ...
Step-by-step explanation:
2/3 is a repeating decimal: 0.66666... Round where you like. The rounding is usually in the 2nd or 3rd decimal place, depending on the accuracy needed.
... 0.67 or 0.667 . . . . . the decimal fraction of dogs
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<em>Comment on wording</em>
The question asks for the "number of dogs". In the problem statement, we're told that number is 2 (out of 3). Actually, it can be any even integer number (out of 3/2 that many), up to 2/3 of the total dog population (which is estimated at over 520 million).
Had the problem asked for <em>the fraction of dogs</em>, then an appropriate answer is 0.67.