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