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Worst Sillies of All Time
pingpongmerrily 51
N
2 hours ago
by EthanNg6
Share the worst sillies you have ever made!
Mine was probably on the 2024 MathCounts State Target Round Problem 8, where I wrote my answer as a fraction instead of a percent, which cost me a trip to Nationals that year.
Mine was probably on the 2024 MathCounts State Target Round Problem 8, where I wrote my answer as a fraction instead of a percent, which cost me a trip to Nationals that year.
51 replies
SOLVE: CDR style problem quick algebra
ryfighter 6
N
2 hours ago
by EthanNg6
It takes 3 people 10 minutes to mow 2 lawns. How many minutes will it take for 2 people to mow 10 lawns? Express your answer in hours as a decimal.














6 replies
Fun challange problem :)
TigerSenju 32
N
2 hours ago
by maxamc
Scenario:
Master Alchemist Aurelius is renowned for his mastery of elemental fusion. He works with seven fundamental, yet mysterious, elements: Ignis (Fire), Aqua (Water), Terra (Earth), Aer (Air), Lux (Light), Umbra (Shadow), and Aether (Spirit). Each element possesses a unique 'potency' value, a positive integer crucial for his most complex fusions
Aurelius has lost his master log of these potencies. All he has left are seven cryptic scrolls, each containing a precise relationship between the potencies of various elements. He needs these values to complete his Grand Device. Can you help him deduce the exact potency of each element?
The Elements and Their Potencies:
Let I represent the potency of Ignis (Fire).
Let A represent the potency of Aqua (Water).
Let T represent the potency of Terra (Earth).
Let R represent the potency of Aer (Air).
Let L represent the potency of Lux (Light).
Let U represent the potency of Umbra (Shadow).
Let E represent the potency of Aether (Spirit).
The Cryptic Scrolls (System of Equations):
Aurelius's scrolls reveal the following relationships:
The combined potency of Ignis, Aqua, and Terra is equal to the potency of Aer plus Lux, plus a constant of two.
If you sum the potencies of Aqua and Umbra, it precisely equals the sum of Lux and Aether, minus one.
The sum of Terra and Aer potencies is the same as the sum of Ignis, Aqua, and Aether potencies, minus one.
Three times the potency of Ignis, plus the potency of Aer, is equal to the sum of Aqua, Terra, and Aether potencies, plus five.
The difference between Lux and Ignis potencies is identical to the difference between Umbra and Aqua potencies.
The sum of Umbra and Aether potencies, when decreased by the potency of Terra, results in twice the potency of Aqua.
The potency of Ignis added to Lux, minus the potency of Aer, is equivalent to the potency of Aether minus Umbra, plus one.
The Grand Challenge:
Using only the information from the cryptic scrolls, set up and solve the system of seven linear equations to determine the unique positive integer potency value for each of the seven elements: I,A,T,R,L,U,E.
good luck, and whoever finds the potencies first, gets a title of The SYSTEMS OF EQUATIONS MASTER
p.s. Yes, I did just come up with a whole story of words to make a ridiculously long problem, but hey, you're reading this, so you probably have nothing better to be doing. ;)
Master Alchemist Aurelius is renowned for his mastery of elemental fusion. He works with seven fundamental, yet mysterious, elements: Ignis (Fire), Aqua (Water), Terra (Earth), Aer (Air), Lux (Light), Umbra (Shadow), and Aether (Spirit). Each element possesses a unique 'potency' value, a positive integer crucial for his most complex fusions
Aurelius has lost his master log of these potencies. All he has left are seven cryptic scrolls, each containing a precise relationship between the potencies of various elements. He needs these values to complete his Grand Device. Can you help him deduce the exact potency of each element?
The Elements and Their Potencies:
Let I represent the potency of Ignis (Fire).
Let A represent the potency of Aqua (Water).
Let T represent the potency of Terra (Earth).
Let R represent the potency of Aer (Air).
Let L represent the potency of Lux (Light).
Let U represent the potency of Umbra (Shadow).
Let E represent the potency of Aether (Spirit).
The Cryptic Scrolls (System of Equations):
Aurelius's scrolls reveal the following relationships:
The combined potency of Ignis, Aqua, and Terra is equal to the potency of Aer plus Lux, plus a constant of two.
If you sum the potencies of Aqua and Umbra, it precisely equals the sum of Lux and Aether, minus one.
The sum of Terra and Aer potencies is the same as the sum of Ignis, Aqua, and Aether potencies, minus one.
Three times the potency of Ignis, plus the potency of Aer, is equal to the sum of Aqua, Terra, and Aether potencies, plus five.
The difference between Lux and Ignis potencies is identical to the difference between Umbra and Aqua potencies.
The sum of Umbra and Aether potencies, when decreased by the potency of Terra, results in twice the potency of Aqua.
The potency of Ignis added to Lux, minus the potency of Aer, is equivalent to the potency of Aether minus Umbra, plus one.
The Grand Challenge:
Using only the information from the cryptic scrolls, set up and solve the system of seven linear equations to determine the unique positive integer potency value for each of the seven elements: I,A,T,R,L,U,E.
good luck, and whoever finds the potencies first, gets a title of The SYSTEMS OF EQUATIONS MASTER
p.s. Yes, I did just come up with a whole story of words to make a ridiculously long problem, but hey, you're reading this, so you probably have nothing better to be doing. ;)
32 replies
MathDash help
Spacepandamath13 8
N
5 hours ago
by Yiyj
AkshajK ORZ by the way invited me to do MathDash a few months ago and I did try it one day but haven't done it much after (Sorry). Now, I'm getting back into it and finding the format kind of weird. When selecting certain problem type sometimes it lets me pick immediately, other times not. Any fixes?
8 replies
MIT PRIMES STEP
pingpongmerrily 5
N
Yesterday at 4:56 PM
by pingpongmerrily
Anyone else applying? How cooked am I for the placement test... (106.5 AMC 10, 5 AIME, 36/27 States/Nationals)
5 replies
Combi counting
Caasi_Gnow 4
N
Yesterday at 3:49 PM
by Rabbit47
Find the number of different ways to arrange seven people around a circular meeting table if A and B must sit together and C and D cannot sit next to each other. (Note: the order for A and B might be A,B or B,A)
4 replies
Math with Connect4 Boards
Math-lover1 12
N
Yesterday at 2:47 PM
by Math-lover1
Hi! So I was playing Connect4 with my friends the other day and I wondered: how many "legal" arrangements of Connect4 can be reached at the ending position?
We assume that we do not stop the game when there is a four in a row, and we have 21 red pieces and 21 yellow pieces. We also drop the pieces one by one into a standard 7 by 6 board. We can start the game with any color piece.
https://en.wikipedia.org/wiki/Connect_Four
Initial Thoughts
Attempt to use one-to-one correspondences
We assume that we do not stop the game when there is a four in a row, and we have 21 red pieces and 21 yellow pieces. We also drop the pieces one by one into a standard 7 by 6 board. We can start the game with any color piece.
https://en.wikipedia.org/wiki/Connect_Four
Initial Thoughts
This problem seems easy at first; the number of arrangments is simply
However, I quickly saw that some boards

OOOOOOO
OOOOOOO
OOOOOOO
OOOOOOO
OOOOOOO
OOOOOOO
were impossible to construct by just dropping pieces one by one like a normal game.OOOOOOO
OOOOOOO
OOOOOOO
OOOOOOO
OOOOOOO
Attempt to use one-to-one correspondences
After I realized that my Initial Thoughts weren't going to work, I tried to use one-to-one correspondences. I represented the columns as ABCDEFG from left to right and represented dropping the red/yellow pieces as a string of length 21 of these letters. This seemed to solve my problem, but new roadblocks popped up.
Roadblock 1 There is more than one way to represent a certain configuration using this correspondence. A quick example
Roadblock 2 Even if we didn't overcount, we still need to account for the fact that the total number of A, B, C... over both of the strings have to each equal 7. The amount of cases (1 A goes to the red pieces, 6 As go to the yellow pieces,...) would be very difficult to calculate, even using a computer.
Roadblock 1 There is more than one way to represent a certain configuration using this correspondence. A quick example
red pieces fill all the left 3 columns, yellow pieces fill all the right 3 columns
shows that we overcount some configurations by using this method.Roadblock 2 Even if we didn't overcount, we still need to account for the fact that the total number of A, B, C... over both of the strings have to each equal 7. The amount of cases (1 A goes to the red pieces, 6 As go to the yellow pieces,...) would be very difficult to calculate, even using a computer.
12 replies
The daily problem!
Leeoz 216
N
Yesterday at 1:42 PM
by kjhgyuio
Every day, I will try to post a new problem for you all to solve! If you want to post a daily problem, you can! :)
Please hide solutions and answers, hints are fine though! :)
Problems usually get harder throughout the week, so Sunday is the easiest and Saturday is the hardest!
Past Problems!
Please hide solutions and answers, hints are fine though! :)
Problems usually get harder throughout the week, so Sunday is the easiest and Saturday is the hardest!
Past Problems!
[quote=March 21st Problem]Alice flips a fair coin until she gets 2 heads in a row, or a tail and then a head. What is the probability that she stopped after 2 heads in a row? Express your answer as a common fraction.[/quote]
Answer
[quote=March 22nd Problem]In a best out of 5 math tournament, 2 teams compete to solve math problems, with each of the teams having a 50% chance of winning each round. The tournament ends when one team wins 3 rounds. What is the probability that the tournament will end before the fifth round? Express your answer as a common fraction.[/quote]
Answer
[quote=March 23rd Problem]The equations of
and
intersect at the point
. What is the value of
?[/quote]
Answer
[quote=March 24th Problem]Anthony rolls two fair six sided dice. What is the sum of all the different possible products of his rolls?[/quote]
Answer
[quote=March 25th Problem]If
, find the value of
.[/quote]
Answer
[quote=March 26th Problem]There is a group of 6 friends standing in line. However, 3 of them don't want to stand next to each other. In how many ways can they stand in line?[/quote]
Answer
[quote=March 27th Problem]Two real numbers,
and
are chosen from 0 to 1. What is the probability that their positive difference is more than
?[/quote]
Answer
[quote=March 28th Problem]What is the least possible value of the expression
?[/quote]
Answer
[quote=March 29th Problem]How many integers from 1 to 2025, inclusive, contain the digit “1”?[/quote]
Answer
[quote=April 3rd Problem]In
families, there are
children respectively. If a random child from any of the families is chosen, what is the probability that the child has
siblings? Express your answer as a common fraction.[/quote]
Answer
[quote=April 5th Problem]A circle with a radius of 3 units is centered at the point (0,0) on the coordinate plane. How many lattice points, points which both of the coordinates are integers, are strictly inside the circle?[/quote]
Answer
[quote=April 6th Problem]If the probability that someone asks for a problem is
, find the probability that out of
people, exactly
of them ask for a problem.[/quote]
Answer
[quote=April 8th Problem]Find the value of
such that
.[/quote]
Answer
[quote=April 9th Problem]In unit square
, point
lies on diagonal
such that
. Find the area of quadrilateral
.[/quote]
Answer
[quote=April 10th Problem]An function in the form
has
,
, and
. Find the value of
.[/quote]
Answer
Answer

[quote=March 22nd Problem]In a best out of 5 math tournament, 2 teams compete to solve math problems, with each of the teams having a 50% chance of winning each round. The tournament ends when one team wins 3 rounds. What is the probability that the tournament will end before the fifth round? Express your answer as a common fraction.[/quote]
Answer

[quote=March 23rd Problem]The equations of




Answer

[quote=March 24th Problem]Anthony rolls two fair six sided dice. What is the sum of all the different possible products of his rolls?[/quote]
Answer

[quote=March 25th Problem]If


Answer

[quote=March 26th Problem]There is a group of 6 friends standing in line. However, 3 of them don't want to stand next to each other. In how many ways can they stand in line?[/quote]
Answer

[quote=March 27th Problem]Two real numbers,



Answer

[quote=March 28th Problem]What is the least possible value of the expression

Answer

[quote=March 29th Problem]How many integers from 1 to 2025, inclusive, contain the digit “1”?[/quote]
Answer

[quote=April 3rd Problem]In



Answer

[quote=April 5th Problem]A circle with a radius of 3 units is centered at the point (0,0) on the coordinate plane. How many lattice points, points which both of the coordinates are integers, are strictly inside the circle?[/quote]
Answer

[quote=April 6th Problem]If the probability that someone asks for a problem is



Answer

[quote=April 8th Problem]Find the value of


Answer

[quote=April 9th Problem]In unit square





Answer

[quote=April 10th Problem]An function in the form





Answer

216 replies
