2020 AMC 8 Problems/Problem 15
Contents
Problem
Suppose of equals of What percentage of is
Solution 1
Since , multiplying the given condition by shows that is percent of .
Solution 2
Letting (without loss of generality), the condition becomes . Clearly, it follows that is of , so the answer is .
Solution 3
We have and , so . Solving for , we multiply by to give , so the answer is .
Solution 4
We are given , so we may assume without loss of generality that and . This means , and thus the answer is .
Solution 5
of is , and of is . We put and into an equation, creating because equals . Solving for , dividing to both sides, we get , so the answer is .
Solution 6
of can be written as , or . of can similarly be written as , or . So now, . Using cross-multiplication, we can simplify the equation as: . Dividing both sides by , we get: . is the same thing as , so the answer is .
Video Solution
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Video Solution
Video Solution by Interstigation
https://youtu.be/YnwkBZTv5Fw?t=665
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Video Solution (CLEVER MANIPULATIONS!!!)
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See also
2020 AMC 8 (Problems • Answer Key • Resources) | ||
Preceded by Problem 14 |
Followed by Problem 16 | |
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