The number of proper subsets of the set $\{1, 2, 3\}$ is

If $X = \{a, b, c, d\}$ and $Y = \{f, b, d, g\},$ find $X - Y$.

Find the union of each of the following pairs of sets:
$A = \{1, 2, 3\}, B = \varnothing$

Let $S = \{1, 2, 3, \ldots, n\}$ and $A = \{(a, b) \mid 1 \leq a, b \leq n\} = S \times S$. $A$ subset $B$ of $A$ is said to be a good subset if $(x, x) \in B$ for every $x \in S$. Then,the number of good subsets of $A$ is

Make correct statements by filling in the symbols $\subset$ or $\not\subset$ in the blank spaces:
$\{ x:x \text{ is a student of class } XI \text{ of your school} \} \dots \{ x:x \text{ is a student of your school} \}$

The number of non-empty subsets of the set $\{1, 2, 3, 4\}$ is