9/1/2025 Student Reflection Note from H

2018 AMC 12A Notes 🎉

😊 Only 2 Wrong — Great Job!

Wrong

• 22: Not sure how to express √abi cleanly.
      Couldn’t manage complex numbers or split the area into 4 pieces.
• 25: Was able to get the powers of 10 and simplify, but not the final casework step.

Right

15, 16, 17, 18, 19, 20, 21, 23, 24

8/31/2015 Student reflection notes from H

2019 AMC 12B Notes

Problems 20–25 → Wrong

• 20: Tried coordinate bash but didn’t realize AOBX is cyclic.
• 21: Very close, but made a mistake in casework.
• 22: No idea how to estimate.
• 24: Confusing — unsure how to approach.
• 25: Imaginary numbers solution was smart.
      Also homothety solution was smart too.

Problems 15–19, 23 → Right

8/23/2025 student reflection notes from H ～ Welcome back to the States.

2019 AMC 12A – Reflection Log

Quick notes on misses, themes, and time sinks.

Incorrect

• #22. Problem and Solutions
• #24. Found all prime exceptions but missed 4 — Problem and Solutions
• #25. Got after hint → need work on angle chasing in cyclic quadrilaterals — Problem and Solutions 

Correct

Problems solved:

#15 #16 #17 #18 #19 #20 #21 #23

• #17 → learn Newton's Sums
• #23 → algebra took a long time.

Next Steps

• Drill Newton’s Sums identities; derive first 3–4 power sums using Vieta.
• Re-check prime-exception logic; include 2 and 4 in prime-exception checklist.
• Daily 10-min cyclic quadrilateral angle-chasing (use Ptolemy, equal angles, arc marks).
• Practice pacing to avoid #17-style time sinks; enforce a 2-minute “move on” rule.
• Algebra endurance reps (substitution, factoring patterns), especially for de-jangling #23-type problems.

8/19/2025 student reflection notes from H

2020 AMC 12B Reflections

Wrong Questions

• Q19: Not sure how to approach. My casework method was too complicated.
• Q21: Solution made sense. I made the substitution u = 70n + 50, but couldn’t expand it properly.
• Q23: Saw that n = 2, n = 3 worked, but I couldn’t eliminate later cases of n ≥ 4.
• Q25: Solution seemed easy, but I didn’t see the graphical method earlier. I have to get better at identifying that.

Correct Questions

• Q15: Solved correctly.
• Q16: Solved correctly.
• Q17: Solved correctly.
• Q18: Solved correctly.
• Q20: Solved correctly.
• Q22: Solved correctly.
• Q24: Solved correctly.

8/15/2025 2020 AMC 12 A student reflection notes from H while in India

2020 AMC 12A Log

Wrong

• Q18 – Tried other equation → could not solve
• Q23 – Hard casework (I could guess if correct, more of a check)
• Q24 – Weird set, specialized translations in geometric problem
• Q25 – Really hard Q. Required graphing + adaptation for 2π trap but not confident/solid

Right

• Q15
• Q16
• Q17
• Q19
• Q20
• Q21
• Q22

8/6/2025 2014 AMC 12 B student reflection notes from H while in India :)

2014 AMC 12B Log

Correct:

• 15
• 16
• 17
• 18 – took time
• 19
• 20
• 22 – time-sink
• 24
• 25

Wrong:

• 21 – struggled with too many variables
• 23 – no idea how to approach

8/1/2025 2014 AMC 12 A student reflection notes from H

2014 AMC 12A — Log

Incorrect Problems

Problem 20

• The lengths are totally random
• Why are they rotated?

Problem 23

• No comment

Problem 25

• Weird parabola
• Not sure how to solve

Correct Problems

• Problem 15
• Problem 16
• Problem 17
• Problem 18 — Took time
• Problem 19
• Problem 21 — Hard b/c of endpoint → took a while; Quick inside a hard transformation
• Problem 22 — Took time
• Problem 24 — Graphed it to solve

7/28/2025 2013 AMC 12 B student reflection notes from H

2013 AMC 12B LOG

Incorrect Problems

• Problem 23 – No idea how to start
• Problem 24 – Almost got it through angle chasing
• Problem 25 – Very close, right idea but missed a few cases

Correct Problems

Problems solved correctly: 15, 16, 17, 18, 19, 20, 21, 22

• Problem 17 – Should learn Cauchy-Schwarz
• Problem 20 – Ran out of time

7/25/2025 H 2013 12 A reflection notes

2013 AMC 12A Log

Incorrect Problems

• Problem 20 – Totally confused
• Problem 24 – Right idea but casework had too many cases
• Problem 25 – No idea how to start

Correct Problems

Problems solved correctly: 15, 16, 17, 18, 19, 21, 22, 23

• Problem 16 – Took too long
• Problem 23 – Angle chasing was hard
• Had to look at answer choices

7/12/2025 2012 AMC 12A H reflection notes

2012 AMC 12 A Reflection Notes

Correct Answers: Questions 15–21

• Questions: 15, 16, 17, 18, 19, 20, 21
• Note on #16: Took time on one question using the Law of Cosines

Unanswered but Attempted: Questions 22, 23

• Q22 & Q23:
• Able to solve with help from solution
• Need to improve:
  • Organized counting of objects
  • 3D visualization skills
• Q23 Additional Note:
• Not able to solve during the test
• Watched a video solution afterward—it made sense, but I wouldn’t have made that connection under time pressure

Unanswered: Questions 24, 25

• Q24:
• Not able to compare exponents correctly
• Had to look at the solution to understand
• It was a complicated question
• Q25:
• Unable to solve even after reviewing the solution
• Gaps in understanding—don’t think I could have arrived at that solution myself
• Struggled with 3D visualization and drawing the necessary graph

7/8/2025 2011 AMC 12B H reflection notes

Q16 → Wrong due to silly mistake

Skipped Q20

• Time-sink solution requires heavy observation and quick identification.
• Involves quick use of inscribed angles and arcs.

Q25 → Not enough time

Was not able to solve; did not understand substitution of
n → n-k in the solution + solution video.
Redo!

Q24 Notes:

• Easy algebra but looked difficult at first.
• Just required extra time to complete — able to solve afterwards.

Q15, Q17, Q18, Q19, Q21, Q22, Q23 → Correct

• Q17: Online solution took a long time
• I had the fastest solution : the solution was first finding g(f(x)) = 10x-1, then subbing in the 1 to get h_1(1)=9, then continuously subbing 9 back into 10x-1 so it becomes 9, 89, 899, 8999….
• Q19: Took a long time
• Found faster solution but took time to get to it: this was a least upper bound question for the slope which hits the next lattice point. If I had the answers, it would have been easier to substitute them back into and find which one would work, but I had hidden the answers. What I did next was find a few of the closest points to 102, 50 which the slope would first intersect and the slope would be as close to 1/2 as possible. After testing a few values in the form of (n/1)/(2n+1) and (n+1)/(2n) which give values close to 1/2, 50/99 was the least of these.

H. a 10th grader student reflection notes

 6/17/2025 2010 AMC 12A

 

6/24/2025  2010 AMC 12 B