If $A = \{ 3, 5, 7, 9, 11 \}$, $B = \{7, 9, 11, 13\}$, $C = \{11, 13, 15\}$ and $D = \{15, 17\}$; find (iii) $A \cap C \cap D$

Write the following sets in roster form: (i) $A = \{x : x$ is an integer and $–3 \le x < 7\}$

Which of the following are sets ? Justify your answer. (i) The collection of all the months of a year beginning with the letter J.

Let $U = \{ 1, 2, 3, 4, 5, 6, 7, 8, 9 \}$, $A = \{ 1, 2, 3, 4\}$, $B = \{ 2, 4, 6, 8 \}$ and $C = \{ 3, 4, 5, 6 \}$. Find (ii) B′

List all the elements of the following sets : (iv) $D = \{x : x$ is a letter in the word “LOYAL”\}

Write the following intervals in set-builder form : (iv) [–23, 5)

Let $A = \{1, 2, 3, 4, 5, 6\}$. Insert the appropriate symbol $\in$ or $\notin$ in the blank spaces: (vi) 10. . .A

Find the union of each of the following pairs of sets : (i) $X = \{1, 3, 5\} Y = \{1, 2, 3\}$

Let $A = \{ 1, 2, \{ 3, 4 \}, 5 \}$. Which of the following statements are incorrect and why? (viii) \{1, 2, 3\} $\subset$ $A$

In the following, state whether $A = B$ or not: (iii) $A = \{2, 4, 6, 8, 10\}$ $B = \{ x : x$ is positive even integer and $x \le 10\}$

From the sets given below, select equal sets : $A = \{ 2, 4, 8, 12\}$, $B = \{ 1, 2, 3, 4\}$, $C = \{ 4, 8, 12, 14\}$, $D = \{ 3, 1, 4, 2\}$ $E = \{–1, 1\}$, $F = \{ 0, a\}$, $G = \{1, –1\}$, $H = \{ 0, 1\}$

Which of the following are sets ? Justify your answer. (vi) A collection of novels written by the writer Munshi Prem Chand.

Decide, among the following sets, which sets are subsets of one and another: $A = \{ x : x \in R$ and $x$ satisfy $x^2 – 8x + 12 = 0 \}$, $B = \{ 2, 4, 6 \}$, $C = \{ 2, 4, 6, 8, . . . \}$, $D = \{ 6 \}$.

Which of the following are sets ? Justify your answer. (ii) The collection of ten most talented writers of India.

If $A = \{3, 6, 9, 12, 15, 18, 21\}$, $B = \{ 4, 8, 12, 16, 20 \}$, $C = \{ 2, 4, 6, 8, 10, 12, 14, 16 \}$, $D = \{5, 10, 15, 20 \}$; find (iii) $A – D$

If $U = \{1, 2, 3, 4, 5, 6, 7, 8, 9 \}$, $A = \{2, 4, 6, 8\}$ and $B = \{ 2, 3, 5, 7\}$. Verify that (ii) $(A \cap B)′ = A′ \cup B′$

Let $A = \{ 1, 2, \{ 3, 4 \}, 5 \}$. Which of the following statements are incorrect and why? (vii) \{1, 2, 5\} $\in$ $A$

Which of the following pairs of sets are disjoint (ii) $\{ a, e, i, o, u \}$ and $\{ c, d, e, f \}$

If $A = \{3, 6, 9, 12, 15, 18, 21\}$, $B = \{ 4, 8, 12, 16, 20 \}$, $C = \{ 2, 4, 6, 8, 10, 12, 14, 16 \}$, $D = \{5, 10, 15, 20 \}$; find (vii) $B – C$

If $A = \{ 3, 5, 7, 9, 11 \}$, $B = \{7, 9, 11, 13\}$, $C = \{11, 13, 15\}$ and $D = \{15, 17\}$; find (ii) $B \cap C$