Difference between revisions of "2024 AMC 8 Problems/Problem 4"

(Problem)
(wapjgpoaewhgawehgoihewoighoiwhg[owrh[oigawh[oghw[aw)
Line 1: Line 1:
 
==Problem==
 
==Problem==
 
When Yunji added all the integers from <math>1</math> to <math>9</math>, she mistakenly left out a number. Her incorrect sum turned out to be a square number. What number did Yunji leave out?
 
When Yunji added all the integers from <math>1</math> to <math>9</math>, she mistakenly left out a number. Her incorrect sum turned out to be a square number. What number did Yunji leave out?
 
==wapjgpoaewhgawehgoihewoighoiwhg[owrh[oigawh[oghw[aw==
 
Roses are red
 
 
violets are blue
 
 
Grass is green
 
 
Chair
 
:skull:
 
  
 
==Solution 3==
 
==Solution 3==

Revision as of 10:41, 13 February 2024

Problem

When Yunji added all the integers from $1$ to $9$, she mistakenly left out a number. Her incorrect sum turned out to be a square number. What number did Yunji leave out?

Solution 3

🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿🗿

-iamcalifornia'sresidentidiot

Therefore the pythagorean theorem is 9+10=21

Solution 4

The sum of digits 1-9 is 45, 45-9=36 36=6^2 Therefore, the solution is that the integer she forgot was 9.

Video Solution 1 (Simple and Fast) by Parshwa

https://youtu.be/Qrf4GTDjjXs

Video Solution 2 (easy to digest) by Power Solve

https://youtu.be/HE7JjZQ6xCk?si=sTC7YNSmfEOMe4Sn&t=179

Video Solution by Math-X (First fully understand the problem!!!)

https://youtu.be/BaE00H2SHQM?si=9ZUxEGmGam7il9xr&t=907

~Math-X


Video Solution by NiuniuMaths (Easy to understand!)

https://www.youtube.com/watch?v=Ylw-kJkSpq8

~NiuniuMaths

Video Solution 2 by SpreadTheMathLove

https://www.youtube.com/watch?v=L83DxusGkSY

Video Solution by CosineMethod [🔥Fast and Easy🔥]

https://www.youtube.com/watch?v=9v5q5DxeriM

Video Solution by Intersigation

https://youtu.be/ktzijuZtDas&t=232

See Also

2024 AMC 8 (ProblemsAnswer KeyResources)
Preceded by
Problem 3
Followed by
Problem 5
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