Difference between revisions of "2009 AMC 8 Problems/Problem 17"

(Solution 2 (Using Answer Choices))
(Solution)
Line 11: Line 11:
 
==Video Solution (XXX)==
 
==Video Solution (XXX)==
 
https://www.youtube.com/watch?v=ZuSJdf1zWYw  ~David
 
https://www.youtube.com/watch?v=ZuSJdf1zWYw  ~David
 
==Solution==
 
The prime factorization of <math>360=2^3 \cdot 3^2 \cdot 5</math>. If a number is a perfect square, all of the exponents in its prime factorization must be even. Thus we need to multiply by a 2 and a 5, for a product of 10, which is the minimum possible value of x. Similarly, y can be found by making all the exponents divisible by 3, so the minimum possible value of <math>y</math> is <math>3 \cdot 5^2=75</math>. Thus, our answer is <math>x+y=10+75=\boxed{\textbf{(B)}\ 85}</math>.
 
  
 
==:)==
 
==:)==

Revision as of 22:02, 17 January 2025

Problem

The positive integers $x$ and $y$ are the two smallest positive integers for which the product of $360$ and $x$ is a square and the product of $360$ and $y$ is a cube. What is the sum of $x$ and $y$?

$\textbf{(A)}\   80    \qquad \textbf{(B)}\    85   \qquad \textbf{(C)}\    115   \qquad \textbf{(D)}\    165   \qquad \textbf{(E)}\    610$

Video Solution (XXX)

https://www.youtube.com/watch?v=ZuSJdf1zWYw ~David

:)

See Also

2010 AMC 8 (ProblemsAnswer KeyResources)
Preceded by
Problem 16
Followed by
Problem 18
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

The problems on this page are copyrighted by the Mathematical Association of America's American Mathematics Competitions. AMC logo.png