2020 AMC 8 Problems/Problem 15
Contents
- 1 Problem
- 2 Solution 1
- 3 Solution 2
- 4 Solution 3
- 5 Solution 4
- 6 Solution 5
- 7 Solution 6
- 8 Video Solution by NiuniuMaths (Easy to understand!)
- 9 Video Solution by Math-X (First understand the problem!!!)
- 10 Video Solution (🚀Very Fast🚀)
- 11 Video Solution
- 12 Video Solution
- 13 Video Solution by Interstigation
- 14 See also
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 by NiuniuMaths (Easy to understand!)
https://www.youtube.com/watch?v=bHNrBwwUCMI
~NiuniuMaths
Video Solution by Math-X (First understand the problem!!!)
https://youtu.be/UnVo6jZ3Wnk?si=fRl03D9Q1KAdDtXz&t=2346
~Math-X
Video Solution (🚀Very Fast🚀)
~Education, the Study of Everything
Video Solution
~savannahsolver
Video Solution
Video Solution by Interstigation
https://youtu.be/YnwkBZTv5Fw?t=665
~Interstigation
See also
2020 AMC 8 (Problems • Answer Key • Resources) | ||
Preceded by Problem 14 |
Followed by Problem 16 | |
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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