To find the number of members who can play only tennis, we apply the principle of inclusion-exclusion to calculate the number of members who can play any of the games. Let:
Applying the principle of inclusion-exclusion:
\( N(F \cup T \cup C) = F + T + C - FT - TC - FC + N(F \cap T \cap C) \)
where \(N(F \cap T \cap C)\) is the number of members who can play all three games. Every member plays at least one game, so \( N(F \cup T \cup C) = 256 \).
Substitute the known values:\( 256 = 144 + 123 + 132 - 58 - 25 - 63 + N(F \cap T \cap C) \)
\( 256 = 339 - 146 + N(F \cap T \cap C) \)
\( 256 = 193 + N(F \cap T \cap C) \)
\( N(F \cap T \cap C) = 256 - 193 = 63 \)
Now, calculate the number of members who can play only tennis:
Therefore, the number of members who can play only tennis is 43.
Let \( A = (1, 2, 3, \dots, 20) \). Let \( R \subseteq A \times A \) such that \( R = \{(x, y) : y = 2x - 7 \} \). Then the number of elements in \( R \) is equal to:
Let $A = \{5n - 4n - 1 : n \in \mathbb{N}\}$ and $B = \{16(n - 1): n \in \mathbb{N}\}$ be sets. Then: