Highest voted questions in Discrete Mathematics

43 votes
2 answers
102
The number of possible commutative binary operations that can be defined on a set of $n$ elements (for a given $n$) is ___________.
43 votes
4 answers
104
43 votes
11 answers
106
43 votes
6 answers
108
43 votes
3 answers
112
43 votes
8 answers
113
43 votes
4 answers
116
Match the pairs in the following questions by writing the corresponding letters only.$$\begin{array}{|c|l|c|l|} \hline A. & \text{The number of distinct binary tree} & P....
42 votes
11 answers
118
42 votes
4 answers
120
Out of a group of $21$ persons, $9$ eat vegetables, $10$ eat fish and $7$ eat eggs. $5$ persons eat all three. How many persons eat at least two out of the three dishes?