Difference between revisions of "2019 AMC 8 Problems/Problem 15"

m (Problem 15: added extra line between problem & ans choices to make formatting better on AMCTrivial)
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<math>\frac{14}{50}=\boxed{\textbf{(B)}\frac{7}{25}}</math>
 
<math>\frac{14}{50}=\boxed{\textbf{(B)}\frac{7}{25}}</math>
  
==Solution Explained==
+
==Video Solutions==
 +
=Solution Explained=
 
https://youtu.be/gOZOCFNXMhE ~ The Learning Royal
 
https://youtu.be/gOZOCFNXMhE ~ The Learning Royal
  
==Video Solution by OmegaLearn==
+
=Video Solution by OmegaLearn=
 
https://youtu.be/6xNkyDgIhEE?t=252
 
https://youtu.be/6xNkyDgIhEE?t=252
  
 
~ pi_is_3.14
 
~ pi_is_3.14
  
==Video Solution==
+
=Video Solution=
 
https://www.youtube.com/watch?v=gKlYlAiBzrs  
 
https://www.youtube.com/watch?v=gKlYlAiBzrs  
  
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-Happytwin
 
-Happytwin
  
== Video Solution ==
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= Video Solution =
  
 
Solution detailing how to solve the problem: https://www.youtube.com/watch?v=omRgmX7KXOg&list=PLbhMrFqoXXwmwbk2CWeYOYPRbGtmdPUhL&index=16
 
Solution detailing how to solve the problem: https://www.youtube.com/watch?v=omRgmX7KXOg&list=PLbhMrFqoXXwmwbk2CWeYOYPRbGtmdPUhL&index=16
  
==Video Solution==
+
=Video Solution=
 
https://youtu.be/9nbaMSAQCNU
 
https://youtu.be/9nbaMSAQCNU
  
 
~savannahsolver
 
~savannahsolver
  
==Video Solution (MOST EFFICIENT+ CREATIVE THINKING!!!)==
+
=Video Solution (MOST EFFICIENT+ CREATIVE THINKING!!!)=
 
https://youtu.be/cK_mfkZ_rYM
 
https://youtu.be/cK_mfkZ_rYM
  
 
~Education, the Study of Everything
 
~Education, the Study of Everything
  
==Video Solution by The Power of Logic(Problem 1 to 25 Full Solution)==
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=Video Solution by The Power of Logic(Problem 1 to 25 Full Solution)=
 
https://youtu.be/Xm4ZGND9WoY
 
https://youtu.be/Xm4ZGND9WoY
  

Revision as of 15:48, 29 December 2023

Problem 15

On a beach $50$ people are wearing sunglasses and $35$ people are wearing caps. Some people are wearing both sunglasses and caps. If one of the people wearing a cap is selected at random, the probability that this person is also wearing sunglasses is $\frac{2}{5}$. If instead, someone wearing sunglasses is selected at random, what is the probability that this person is also wearing a cap?

$\textbf{(A) }\frac{14}{85}\qquad\textbf{(B) }\frac{7}{25}\qquad\textbf{(C) }\frac{2}{5}\qquad\textbf{(D) }\frac{4}{7}\qquad\textbf{(E) }\frac{7}{10}$

Solution 1

The number of people wearing caps and sunglasses is $\frac{2}{5}\cdot35=14$. So then, 14 people out of the 50 people wearing sunglasses also have caps.

$\frac{14}{50}=\boxed{\textbf{(B)}\frac{7}{25}}$

Video Solutions

Solution Explained

https://youtu.be/gOZOCFNXMhE ~ The Learning Royal

Video Solution by OmegaLearn

https://youtu.be/6xNkyDgIhEE?t=252

~ pi_is_3.14

Video Solution

https://www.youtube.com/watch?v=gKlYlAiBzrs

~ MathEx

https://www.youtube.com/watch?v=afMsUqER13c

Another video

https://youtu.be/37UWNaltvQo

-Happytwin

Video Solution

Solution detailing how to solve the problem: https://www.youtube.com/watch?v=omRgmX7KXOg&list=PLbhMrFqoXXwmwbk2CWeYOYPRbGtmdPUhL&index=16

Video Solution

https://youtu.be/9nbaMSAQCNU

~savannahsolver

Video Solution (MOST EFFICIENT+ CREATIVE THINKING!!!)

https://youtu.be/cK_mfkZ_rYM

~Education, the Study of Everything

Video Solution by The Power of Logic(Problem 1 to 25 Full Solution)

https://youtu.be/Xm4ZGND9WoY

~Hayabusa1

See Also

2019 AMC 8 (ProblemsAnswer KeyResources)
Preceded by
Problem 14
Followed by
Problem 16
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
All AJHSME/AMC 8 Problems and Solutions

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