solve a cool problem and explore a new idea every week! A new problem and the solution to last week’s problem will be posted here every week. **Currently, the Problem of the Week is on hold. In the meantime, PoTW #31 has an indefinite submission period: solve these three problems featured on math t-shirts!**

**Current PoTW: Week of X/X/2022 PoTW #X**

Click here to submit a solution to this week’s PoTW!

**Solution to last week’s PoTW: **

## Problems archive:

3/4/2022 PoTW #30: CMU Helicopter

2/18/2022 PoTW #29: Locus Practice

1/28/2022 PoTW #28: moving points (this is clickbait)

1/21/2022 PoTW #27: Wait. It’s coordinates? It always has been…

1/14/2022 PoTW #26: positive integers only

1/7/2022 PoTW #25: Double Factorial Sum

12/31/2021 PoTW #24: Iranian brain teaser

12/17/2021 PoTW #23: Adventures on the 9-point Circle, part 1

12/3/2021 PoTW #22: Cool Ellipse problem

11/26/2021 PoTW #21: Contrived Turkey

11/11/2021 PoTW #19: WELCOME BACK: AMC SEASON (:

9/25/2021 PoTW #18: AMC Week 1

9/16/2021 PoTW #17: 777 (part 2)

9/2/2021 PoTW #15: two practice alg problems

8/26/2021 PoTW #14: Factor Fest

8/19/2021 PoTW #13: Welcome to Math Team Airlines

8/12/2021 PoTW #12: Greatest Divisor

7/29/2021 PoTW #10: Graveling Graphs

7/22/2021 PoTW #9: It’s Coming Rome

7/1/2021 PoTW #6: Plushee Paradise

6/17/2021 PoTW #4: Phun Physics Phridays

6/10/2021 PoTW #3: The Sweetest Strawberry

6/3/2021 PoTW #2: Catalan Craziness

5/27/2021 PoTW #1: Vexing Hexagon

## Solutions archive:

all solutions try to cover a variety of different approaches. sometimes solutions include more in-depth expositions into how a more general problem solving technique applies to the specific problem solution. solutions featuring these more detailed expositions are denoted with *.

1/14/2022 PoTW #26: positive integers only (solution)

1/7/2022 PoTW #25: Double Factorial Sum (solution)

12/31/2021 PoTW #24: Iranian Brain Teaser (solution)

12/17/2021 PoTW #23: Adventures on the 9-Point circle, part 1 (solution)

*12/3/2021 PoTW #22: Cool Ellipse Problem (solution) — ellipse properties (solvers: Jeffrey Chen, Jack Chen)

11/26/2021 PoTW #21: Contrived Turkey (solution)

*11/19/2021 PoTW #20: Poly Fib (solution) — theory of finite differences

11/11/2021 PoTW #19: WELCOME BACK: AMC SEASON (: (solution)

9/25/2021 PoTW #18: AMC Week 1 (solution)

9/16/2021 PoTW #17: 777 Pt. 2 (solution) (solvers: Jeffrey Chen, Jaden Chen)

9/9/2021 PoTW #16: 777 (solution) (solvers: Faizaan Siddique, Shaurya Agrawal, Jaden Chen, Benjamin Chen)

9/2/2021 PoTW #15: two practice alg problems (solution) (solvers: Jeffrey Chen)

8/26/2021 PoTW #14: Factor Fest (solution)

8/19/2021 PoTW #13: Welcome to Math Team Airlines (solution) (solvers: Faizaan Siddique, Brady Rivkin, Benjamin Chen, Anonymous, Anonymous)

8/12/2021 PoTW #12: Greatest Divisor (solution) (solvers: Faizaan Siddique)

8/5/2021 PoTW #11: OhMo (solution)

7/29/2021 PoTW #10: Graveling Graphs (solution) (solvers: Benjamin Chen)

7/22/2021 PoTW #9: It’s Coming Rome (solution)

*7/15/2021 PoTW #8: Oh Titu… (solution) — titu’s favorite factoring trick

*7/8/2021 PoTW #7: Blame Jack (solution) — harmonic quadrilaterals, mixtilinear incircles

7/1/2021 PoTW #6: Plushee Paradise (solution)

6/24/2021 PoTW #5: Algebra?? (solution)

6/17/2021 PoTW #4: Phun Physics Phridays (solution) (solvers: Jack Chen)

6/10/2021 PoTW #3: The Sweetest Strawberry (solution) (solvers: Jack Chen)

*6/3/2021 PoTW #2: Catalan Craziness (solution) — catalan numbers and generalizations

*5/27/2021 PoTW #1: Vexing Hexagon (solution) — power of a point (solvers: Jessica He, Jack Chen)

For hints or other inquiries about the PoTW, email: andliu22@students.d125.org