Elaine drives her car 180 miles and has an average of a certain speed. If the average speed had been 5mph more, she could have traveled 200 miles in the same length of time. What was her average speed?
+14917 What was her average speed?
Hello Guest!
\(xt=180ml\\ t=\dfrac{180ml}{x}\\ (x+5ml/h)t=200ml\\ t=\dfrac{200ml}{x+5ml/h}\\ \dfrac{x+5ml/h}{200ml}=\dfrac{x}{180ml}\ |\ \times ml\)
\(180x+900ml/h=200x\ |\ -180x\\ 900ml/h=20x\ |\ :20 \)
\(x=45ml/h\)
Her average speed was 45ml/h.
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