What are the $5$ different combinations of $4$ numbers that can add to $8, 9, 10$ or $11$?
106445
Dr Math and his family question. How to solve without trial and error?
65802
The number of 5-digit numbers such that their sum of digits is even is?
13420
$10$ Equations in $10$ variables
144025
Number of Solutions in this Number Puzzle
115815
Additive Roman Numeral 4
133932
How many possible combinations in 8 character password?
140858
Number of ways to choose 6 objects when they are of 11 different kinds
57236
How many different combinations of a six sided die rolls equals n
58673
Elements of order 5 in $S_7$, odd permutations of order 4 in $S_4$, and find a specific permutation in $S_7$
60661
How to solve this combination problem quickly?
64985
Get the numbers from (0-30) by using the number $2$ four times
124248
$1+\frac {1}{4}(1+\frac {1}{4}) +\frac {1}{9}(1+\frac {1}{4} +\frac {1}{9})+....$
157280
How do I sum up specific things in Numbers?
126708
Finding the missing digits of $23!$
155496
sum of combinations $\binom n{0} + \binom n{3} + \binom n{6} +... +\binom n{3k}$
8049
Generating Combinations
4301
How many different arrangements?