A car is parked by an owner amongst 25 cars in a row not at the two extremes. On his return he find that exactly 15 places are .
106484
Car parking related probability
45111
Number of Subspaces that contains other Space
22683
There are 10 stations on a circular path
81465
"Each person's car" vs. "each persons' car"
110856
Number of ways to select $K$ people from $N$ people such that at least $r$ people are there in between them
84865
A 5x5 board has 25 cells.The numbers $\{1,2,3,4,5\}$ are written on every row,every column and the two main diagonals.
75678
Dual Commutes with Base Change
134440
An unexpected application of non-trivial combinatorics
152333
A problem based on pigeonhole
33912
Group with 380 elements is not simple.
129568
How many different groups of order $15$ there are?
131885
Show that not all 5 cycles in $A_5$ are conjugate in $A_5$
31340
Concurrent lines proof for a regular 18-gon
121605
A coin tossing game which leads to a contradiction
107674
Find taxicab numbers in $O(n)$ time
80832
Construct a field of 25 elements.
19101
Permutation induced by a partition