2020 AMC 10B Problems/Problem 7
Contents
Problem
How many positive even multiples of less than
are perfect squares?
Solution
Any even multiple of is a multiple of
, so we need to find multiples of
that are perfect squares and less than
. Any solution that we want will be in the form
, where
is a positive integer. The smallest possible value is at
, and the largest is at
(where the expression equals
). Therefore, there are a total of
possible numbers.-PCChess
Video Solution
~IceMatrix
See Also
2020 AMC 10B (Problems • Answer Key • Resources) | ||
Preceded by Problem 6 |
Followed by Problem 8 | |
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