Make correct statements by filling in the symbols $\subset$ or $ \not\subset $ in the blank spaces:
$\{ x:x$ is a student of class $\mathrm{XI}$ of your school $\} \ldots \{ x:x$ student of your school $\} $
Are the following pair of sets equal ? Give reasons.
$A = \{ 2,3\} ,\quad \,\,\,B = \{ x:x$ is solution of ${x^2} + 5x + 6 = 0\} $
Which of the following are sets ? Justify your answer.
The collection of all natural numbers less than $100 .$
Write the following as intervals :
$\{ x:x \in R, - 4\, < \,x\, \le \,6\} $
In each of the following, determine whether the statement is true or false. If it is true, prove it. If it is false, give an example.
If $A \not\subset B$ and $B \not\subset C,$ then $A \not\subset C$