Venn Diagram Flavours
1. **State the problem:** We have 71 guests and three flavors: Mirinda (M), Novida (N), and Fanta (F). We are given information about how many guests prefer combinations of these flavors and need to represent this on a Venn diagram.
2. **Given data:**
- Total guests: 71
- Guests who preferred M and F but not other flavor: 10
- Guests who preferred F and N (including those who might prefer all three): 11
- Guests who preferred M and N but not other flavor: 6
- Guests who preferred F (only F): 26
- Guests who preferred M only: 5
- Guests who preferred F only is double those who preferred N only
3. **Define variables:**
- Let $x$ = number of guests who preferred N only
- Let $y$ = number of guests who preferred all three flavors (M, N, F)
4. **Analyze the data:**
- Guests who preferred F and N includes those who preferred all three, so $F \cap N = 11$ means $y +$ guests who preferred only F and N (no M) = 11
- Guests who preferred M and N but not other flavor = 6 means guests who preferred only M and N (no F) = 6
- Guests who preferred M and F but not other flavor = 10 means guests who preferred only M and F (no N) = 10
5. **Express the sets:**
- $|M \cap N \cap F| = y$
- $|M \cap N \text{ only}| = 6$
- $|M \cap F \text{ only}| = 10$
- $|F \cap N \text{ only}| = 11 - y$
- $|M \text{ only}| = 5$
- $|N \text{ only}| = x$
- $|F \text{ only}| = 2x$ (since F only is double N only)
6. **Total guests equation:**
$$5 + x + 2x + 6 + 10 + (11 - y) + y = 71$$
Simplify:
$$5 + x + 2x + 6 + 10 + 11 - y + y = 71$$
$$5 + 3x + 6 + 10 + 11 = 71$$
$$32 + 3x = 71$$
$$3x = 39$$
$$x = 13$$
7. **Find F only:**
$$F \text{ only} = 2x = 2 \times 13 = 26$$
8. **Find all three flavors (y):**
From $F \cap N = 11$, and $F \cap N \text{ only} = 11 - y$, so $y$ is unknown but must be consistent.
9. **Check total with y:**
Sum of all parts:
$$5 (M only) + 13 (N only) + 26 (F only) + 6 (M \cap N only) + 10 (M \cap F only) + (11 - y) (F \cap N only) + y (M \cap N \cap F) = 71$$
Simplify:
$$5 + 13 + 26 + 6 + 10 + 11 - y + y = 71$$
$$71 = 71$$
This holds for any $y$, so $y$ can be any value from 0 to 11.
10. **Conclusion:**
- $M$ only = 5
- $N$ only = 13
- $F$ only = 26
- $M \cap N$ only = 6
- $M \cap F$ only = 10
- $F \cap N$ only = $11 - y$
- $M \cap N \cap F$ = $y$ (unknown, between 0 and 11)
This information can be represented on a Venn diagram with these values.
**Final answer:**
$$M \text{ only} = 5, \quad N \text{ only} = 13, \quad F \text{ only} = 26,$$
$$M \cap N \text{ only} = 6, \quad M \cap F \text{ only} = 10, \quad F \cap N \text{ only} = 11 - y, \quad M \cap N \cap F = y$$
where $0 \leq y \leq 11$.