+0  
 
0
476
2
avatar

In a 100 meter race, Allen and Bruce reached the finish line in 12 seconds and 15 seconds, respectively. When Allen finished the race, how far was Bruce from the finish line?

Assume that they each move at a constant rate.

 Jul 6, 2020
 #1
avatar+26364 
+2

In a 100 meter race, Allen and Bruce reached the finish line in 12 seconds and 15 seconds, respectively.
When Allen finished the race, how far was Bruce from the finish line?
Assume that they each move at a constant rate.

 

\(v_{\text{Bruce}} = \dfrac{100\ m}{15\ s} \)

 

\(\begin{array}{|rcll|} \hline s_{\text{Bruce}} &=& \dfrac{100\ m}{15\ s} \times (15\ s -12\ s) \\\\ s_{\text{Bruce}} &=& \dfrac{100\ m}{15\ s} \times (3\ s) \\\\ \mathbf{s_{\text{Bruce}}} &=& \mathbf{20\ \text{meter}} \\ \hline \end{array}\)

 

Bruce was \(\mathbf{20\ \text{meter}}\) from the finish line.

 

laugh

 Jul 6, 2020
 #2
avatar+1262 
+3

So we get that the speed of Allen is 100/12=50/6=25/3 and the speed for Bruce is 100/15=20/3 so we have 100-20/3*12=100-80=20 so Bruce was 20 meters from the finish line

 Jul 6, 2020

1 Online Users