Difference between revisions of "2019 AMC 8 Problems/Problem 9"

(Solution 1)
(Solution 2)
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==Solution 2==
 
==Solution 2==
  
The ratio of them is <math>1/2</math>, meaning that the ratio of them will be <math>1(2)/2(2)<cmath>=</cmath>\boxed{\textbf{(B)}\ 1:2}</math>   
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The ratio of the numbers is <math>1/2</math>. Looking closely at the formula <math>r^2 * h * \pi</math>, we see that the <math>r * h * \pi</math> will cancel, meaning that the ratio of them will be <math>1(2)/2(2) = \boxed{\textbf{(B)}\ 1:2}</math>   
  
 
-Lcz
 
-Lcz

Revision as of 17:42, 22 November 2019

Alex and Felicia each have cats as pets. Alex buys cat food in cylindrical cans that are $6$ cm in diameter and $12$ cm high. Felicia buys cat food in cylindrical cans that are $12$ cm in diameter and $6$ cm high. What is the ratio of the volume one of Alex's cans to the volume one of Felicia's cans?

$\textbf{(A) }1:4\qquad\textbf{(B) }1:2\qquad\textbf{(C) }1:1\qquad\textbf{(D) }2:1\qquad\textbf{(E) }4:1$

Solution 1

Using the formula for the volume of a cylinder, we get that the volume of Alex's can is $3^2\cdot12\cdot\pi$, and that the volume of Felicia's can is $6^2\cdot6\cdot\pi$. Now we divide the volume of Alex's can by the volume of Felicia's can, so we get $\frac{1}{2}$, which is $\boxed{\textbf{(B)}\ 1:2}$ ~~SmileKat32

Solution 2

The ratio of the numbers is $1/2$. Looking closely at the formula $r^2 * h * \pi$, we see that the $r * h * \pi$ will cancel, meaning that the ratio of them will be $1(2)/2(2) = \boxed{\textbf{(B)}\ 1:2}$

-Lcz

See Also

2019 AMC 8 (ProblemsAnswer KeyResources)
Preceded by
Problem 8
Followed by
Problem 10
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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