Difference between revisions of "1968 AHSME Problems/Problem 25"

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== Solution ==
 
== Solution ==
 
<math>\fbox{C}</math>
 
<math>\fbox{C}</math>
 
== Solution 2 ==
 
 
Let <math>k</math> denotes the distance Ace needs to run after the <math>y</math> yard. Since the distance they run with same amount of time is proportional to their speed, we have
 
<cmath>\frac{1}{x}=\frac{k}{y+k}</cmath>
 
<cmath>k=\frac{y}{x-1}</cmath>
 
Thus the total distance ran by Flash is
 
<cmath>y+k=y+\frac{y}{x-1}=\frac{xy}{x-1}\boxed{C}</cmath>
 
 
~ Nafer
 
  
 
== See also ==
 
== See also ==

Revision as of 20:22, 17 July 2024

Problem

Ace runs with constant speed and Flash runs $x$ times as fast, $x>1$. Flash gives Ace a head start of $y$ yards, and, at a given signal, they start off in the same direction. Then the number of yards Flash must run to catch Ace is:

$\text{(A) } xy\quad \text{(B) } \frac{y}{x+y}\quad \text{(C) } \frac{xy}{x-1}\quad \text{(D) } \frac{x+y}{x+1}\quad \text{(E) } \frac{x+y}{x-1}$

Solution

$\fbox{C}$

See also

1968 AHSC (ProblemsAnswer KeyResources)
Preceded by
Problem 24
Followed by
Problem 26
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35
All AHSME Problems and Solutions

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