Difference between revisions of "1985 AJHSME Problem 13"

(Created page with "== Problem == If you walk for <math>45</math> minutes at a rate of <math>4 \text{ mph}</math> and then run for <math>30</math> minutes at a rate of <math>10\text{ mph,}</math...")
 
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<math>\text{(A)}\ 3.5\text{ miles} \qquad \text{(B)}\ 8\text{ miles} \qquad \text{(C)}\ 9\text{ miles} \qquad \text{(D)}\ 25\frac{1}{3}\text{ miles} \qquad \text{(E)}\ 480\text{ miles}</math>
 
<math>\text{(A)}\ 3.5\text{ miles} \qquad \text{(B)}\ 8\text{ miles} \qquad \text{(C)}\ 9\text{ miles} \qquad \text{(D)}\ 25\frac{1}{3}\text{ miles} \qquad \text{(E)}\ 480\text{ miles}</math>
  
== Solution ==
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==In-depth Solution by BoundlessBrain!==
 +
https://youtu.be/varobXGlcdU
 +
 
 
Distance is equal to rate multiplied by time:
 
Distance is equal to rate multiplied by time:
 
<cmath>d = \frac{45}{60} \cdot 4 + \frac{30}{60} \cdot 10 = \boxed{8}.</cmath>
 
<cmath>d = \frac{45}{60} \cdot 4 + \frac{30}{60} \cdot 10 = \boxed{8}.</cmath>
 
The answer is <math>\text{(B)}.</math>
 
The answer is <math>\text{(B)}.</math>

Revision as of 15:58, 4 July 2023

Problem

If you walk for $45$ minutes at a rate of $4 \text{ mph}$ and then run for $30$ minutes at a rate of $10\text{ mph,}$ how many miles will you have gone at the end of one hour and $15$ minutes?

$\text{(A)}\ 3.5\text{ miles} \qquad \text{(B)}\ 8\text{ miles} \qquad \text{(C)}\ 9\text{ miles} \qquad \text{(D)}\ 25\frac{1}{3}\text{ miles} \qquad \text{(E)}\ 480\text{ miles}$

In-depth Solution by BoundlessBrain!

https://youtu.be/varobXGlcdU

Distance is equal to rate multiplied by time: \[d = \frac{45}{60} \cdot 4 + \frac{30}{60} \cdot 10 = \boxed{8}.\] The answer is $\text{(B)}.$