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2 votes
2 answers
226 views

Can you pack $53$ bricks of dimensions $1\times 1\times 4$ into a $6\times 6\times 6$ box?

Can you pack 53 bricks of 1×1×4 size into 6×6×6 box? Source: puzzledquant.com My approach: I looked at the solution and visualized the box as $3d$ checkerboard. So in total we have $27$ such $2\...
Charlie's user avatar
  • 305
3 votes
0 answers
92 views

Maximum tiling by Y Hexomino

"Y Hexomino" has a shape as shown in the picture. What is the maximum number of Y Hexomino that can be placed on a $13\times 13$ chessboard, where each Hexomino does not overlap? From the ...
rack's user avatar
  • 183
0 votes
1 answer
149 views

2D packing problem, as a puzzle.

I have discovered a 2D packing problem that I cannot find the tools online to solve, so I have decided to present it to the Mathematics Stack Exchange as a fun puzzle. In this problem there exist 4 ...
AncientShotgun's user avatar
5 votes
0 answers
228 views

Articles from the Journal of Recreational Mathematics from the 1970s

When reading some articles about packing puzzles I regularly stumble accros references from the "Journal of Recreational Mathematics" from the 1970s. I did not found any way of accessing ...
Martin's user avatar
  • 649
5 votes
2 answers
830 views

Number of plates that can be placed on the table so that they neither overlap each other nor the edge of the table?

Table in my room is round in shape and its radius is 15 times the radius of our plates, which are also round in shape. Find the number of plates that can be placed on the table so that they neither ...
Tips's user avatar
  • 388
0 votes
1 answer
238 views

How many balls can fit in a house shaped box?

Consider the following house shaped box with the indicated measures: I need to get the best possible approximation of how many balls of 3 inches of diameter can fit in this box without exceeding the ...
Twnk's user avatar
  • 2,446
0 votes
0 answers
69 views

Help with understanding if my way to solve the riddle works or not

So the riddle i was asked is: you have a circle, with a radius of 9, prove that you cant pack 101 points inside of it, without having at least a pair of dots with a distance less than 2 between them. ...
KlesierTheSurvivor's user avatar
3 votes
1 answer
126 views

Tiling a room when (room and/or tile) dimensions are irrational

My question is inspired by this question. There is a rectangular room of dimension $a \times b$, and there is an unlimited number of rectangular tiles of dimension $c \times d$. You are allowed one ...
antkam's user avatar
  • 15.4k
1 vote
3 answers
518 views

Minimum number of trips for a truck with weight limit of $200$ to transport boxes with weights 81, 73, 67, 49, 37, 34, 30, and 26

My 9-year-old son had the following math problem to solve: A truck can carry $200$kg or less. We have 8 different boxes with given weights: $81$kg, $73$kg, $67$kg, $49$kg, $37$kg, $34$kg, $30$kg, and ...
Blup1980's user avatar
  • 131
3 votes
2 answers
748 views

maximal minimum distance between points in a rectangle of size $17\times 32$

I am training in problem solving and this one greatly resists to my understanding: Given a rectangle with specified length and width, you have to place 5 points in the rectangle such that you ...
user avatar
6 votes
1 answer
388 views

Inequality AM/HM <= (AM/GM)^n with packing problem interpretation

I have stumbled upon the following inequality while exploring "Hoffman's packing problem", which I'm pretty convinced is true, but unable to prove. Let $n \geq 2$ be a natural number and let $x_1, \...
Nikolaj's user avatar
  • 179
6 votes
3 answers
257 views

How many $9\times 9$ squares can I cut from this figure (it's $40\times 38$ without some corners)

Can I cut 16 ones (along the grid)? I've tried to paint some $15$ cells so that every $9\times 9$ square contain only $1$ painted cell (so I prove there can't be $16$), but to no avail. The figure (...
Alexey Burdin's user avatar
21 votes
1 answer
2k views

Why are these geometric problems so hard?

I was surprised to learn that both for the Moving Sofa Problem and Packing 11 Squares solutions have been proposed, but in either case the optimality of the proposed solution is, as of yet, only ...
Řídící's user avatar
  • 3,220
8 votes
1 answer
1k views

Finding the maximum number of $70\times 30$ tiles that can be placed into a $110\times 130$ floor, without trial and error

The following question was asked in a competitive exam Rectangular tiles each of size 70 cm by 30 cm must be laid horizontally on a rectangular floor of size 110 cm by 130 cm, such that the tiles do ...
ILoveStackExchange's user avatar