Question

Two cars traveled equal distances in different amounts of time. Car A traveled the distance in 2 h, and Car B traveled the distance in 1.5 h. Car B traveled 15 mph faster than Car A. How fast did Car B travel? (The formula R⋅T=D , where R is the rate of speed, T is the time, and D is the distance can be used.) Enter your answer for the box.

Answer 1

recall your d = rt, distance = rate * time.

notice, the distance are the same, say it was "d" miles.

and if car A is travelling at a speed of say "r" mph, then B is going at "r+15" mph.


`\bf \begin{array}{lccclll} &\stackrel{miles}{distance}&\stackrel{mph}{rate}&\stackrel{hours}{time}\\ &------&------&------\\ \textit{Car A}&d&r&2\\ \textit{Car B}&d&r+15&1.5 \end{array} \\\\\\ \begin{cases} \boxed{d}=2r\\ d=1.5(r+15)\\ ----------\\ \boxed{2r}=1.5(r+15) \end{cases} \\\\\\ 2r=1.5r+22.5\implies 0.5r=22.5\implies r=\cfrac{22.5}{0.5}\implies \boxed{r=\stackrel{mph}{45}}`

how far is B going? well, r + 15.

Answer 2

Hi there the answer is 60 I took the quiz I hope I helped