The answer is: [B]: " r = dt " .
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Explanation:
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Let us consider the answer choices given:
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The formula is: d = rt ; (that is: "d = r * t ") .
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Side note: In practice, this formula stands for: " distance = rate * time " .
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Consider "choice [A]: d/r = t ; This is true;
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Given: d = rt ;
d/r = rt/ r ; d/r = t . True.
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Consider "Choice [B]: r = dt .
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Given: d = rt ; r = d/t ; {not: " r = dt " }; so this answer seems correct!
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Consider "Choice [C]: d/t = r ;
As shown directly above (that is, considering "Choice B"); r = d/t ; ↔ d/t = r;
which is true.
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Consider "Choice [D]: d / rt = 1 ;
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Given: d = rt ; d/rt = rt/rt ; d/rt = 1 ; since (rt/rt =1); so this is true.
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So, Answer choice: [B]: " r = dt " ; is the correct answer!
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