If $n(A) = 3$ and $n(B) = 6$ and $A \subseteq B$,then the number of elements in $A \cap B$ is:

Let $x_{1}, x_{2}, \ldots, x_{15}$ be $15$ distinct numbers chosen from $1, 2, 3, \ldots, 15$. Then,the value of $(x_{1}-1)(x_{2}-1)(x_{3}-1) \ldots (x_{15}-1)$ is

Write down all the subsets of the following set: $\{a, b\}$

If $aN = \{ ax : x \in N \}$ and $bN \cap cN = dN$,where $b, c \in N$ are relatively prime,then

If $A = \{2, 3, 4, 5, 6\}$,then which of the following statements has a truth value of 'false'?

Write the following as intervals: $\{ x:x \in R, 3 \le x \le 4 \}$