Sports Venn 01C1D3
1. **Problem statement:**
We have 110 members playing at least one of football, basketball, volleyball. Given:
- 20 play football and basketball only
- 15 play football and volleyball only
- 26 play basketball and volleyball only
- $x$ play all three games
- $2x$ play only one game
We want to find how many play basketball altogether.
2. **Formula and rules:**
Using the principle of inclusion-exclusion for three sets:
$$|F \cup B \cup V| = |F| + |B| + |V| - |F \cap B| - |F \cap V| - |B \cap V| + |F \cap B \cap V|$$
Also, total players = 110.
3. **Define variables:**
Let:
- $a$ = number who play only football
- $b$ = number who play only basketball
- $c$ = number who play only volleyball
- Given $a + b + c = 2x$ (only one game players)
4. **Express total players:**
Total = only one game + exactly two games + all three games
$$110 = (a + b + c) + (20 + 15 + 26) + x = 2x + 61 + x = 3x + 61$$
5. **Solve for $x$:**
$$3x + 61 = 110 \implies 3x = 49 \implies x = \frac{49}{3} \approx 16.33$$
Since number of players must be integer, assume $x=16$ (closest integer).
6. **Calculate only one game players:**
$$a + b + c = 2x = 32$$
7. **Find total basketball players:**
Basketball players include:
- Only basketball: $b$
- Football and basketball only: 20
- Basketball and volleyball only: 26
- All three: $x=16$
So total basketball players:
$$b + 20 + 26 + 16 = b + 62$$
8. **Find $b$ using total only one game players:**
We know $a + b + c = 32$, but no further info to separate $a,b,c$.
Assuming equal distribution or no further info, we cannot find exact $b$.
**However, since question asks for basketball players altogether, and only basketball players is $b$, we can express answer as $b + 62$ where $b$ is unknown.**
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**Second problem:**
1. **Problem statement:**
290 readers read at least one of Daily Times (D), Guardian (G), Punch (P).
Given:
- $|D|=181$, $|G|=142$, $|P|=117$
- $|D \cap G|=75$, $|D \cap P|=60$, $|G \cap P|=54$
- Find:
i. Number reading all three papers
ii. Number reading exactly two papers
iii. Number reading exactly one paper
iv. Number reading Guardian alone
2. **Formula:**
Using inclusion-exclusion:
$$|D \cup G \cup P| = |D| + |G| + |P| - |D \cap G| - |D \cap P| - |G \cap P| + |D \cap G \cap P|$$
Since all read at least one paper, total = 290.
3. **Calculate $|D \cap G \cap P|$:**
$$290 = 181 + 142 + 117 - 75 - 60 - 54 + x$$
$$290 = 440 - 189 + x$$
$$290 = 251 + x \implies x = 39$$
4. **Calculate exactly two papers:**
Exactly two = sum of pairwise intersections minus thrice the triple intersection:
$$= (75 + 60 + 54) - 3 \times 39 = 189 - 117 = 72$$
5. **Calculate exactly one paper:**
Exactly one = total - exactly two - all three
$$= 290 - 72 - 39 = 179$$
6. **Calculate Guardian alone:**
$$|G| - |D \cap G| - |G \cap P| + |D \cap G \cap P| = 142 - 75 - 54 + 39 = 52$$
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**Final answers:**
- Basketball players altogether = $b + 62$ where $b$ is unknown
- Number reading all three papers = 39
- Number reading exactly two papers = 72
- Number reading exactly one paper = 179
- Number reading Guardian alone = 52