Difference between revisions of "2007 AIME I Problems/Problem 1"
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== Problem == | == Problem == | ||
| − | How many [[positive]] [[perfect | + | How many [[positive]] [[perfect square]]s less than <math>10^6</math> are [[multiple]]s of <math>24</math>? |
== Solution == | == Solution == | ||
| − | The [[prime factorization]] of <math>24 | + | The [[prime factorization]] of <math>24</math> is <math>2^3\cdot3</math>; thus each square must have 3 factors of <math>2</math> and 1 factor of <math>3</math>. This means that the square is in the form <math>(12c)^2</math>, where c is a positive integer. There are <math>\left\lfloor \frac{1000}{12}\right\rfloor</math> solutions. |
== See also == | == See also == | ||
Revision as of 15:57, 15 March 2007
Problem
How many positive perfect squares less than 
are multiples of 
?
Solution
The prime factorization of is 
; thus each square must have 3 factors of 
and 1 factor of 
. This means that the square is in the form 
, where c is a positive integer. There are 
solutions.
See also
| 2007 AIME I (Problems • Answer Key • Resources) | ||
| Preceded by First Question |
Followed by Problem 2 | |
| 1 • 2 • 3 • 4 • 5 • 6 • 7 • 8 • 9 • 10 • 11 • 12 • 13 • 14 • 15 | ||
| All AIME Problems and Solutions | ||
