1. **State the problem:** We have 30 cupcakes in total.
- 16 cupcakes are iced.
- 3 cupcakes are both iced and contain walnuts.
- 5 cupcakes are neither iced nor contain walnuts.
We want to find the probability that a randomly picked cupcake contains walnuts.
2. **Draw and label the Venn diagram:**
- Let the circle for iced cupcakes have 16 total.
- The intersection (iced and walnuts) is 3.
- Let the number of cupcakes containing walnuts but not iced be $x$.
- Outside both circles are 5 cupcakes.
3. **Calculate the number of cupcakes containing walnuts:**
- Total cupcakes = 30
- Cupcakes neither iced nor walnuts = 5
- Cupcakes iced only = $16 - 3 = 13$
4. **Find $x$ (cupcakes containing walnuts but not iced):**
Total cupcakes = iced only + walnuts only + both + neither
$$30 = 13 + x + 3 + 5$$
Simplify:
$$30 = 21 + x$$
Subtract 21 from both sides:
$$30 - 21 = \cancel{21} + x - 21$$
$$9 = x$$
5. **Calculate total cupcakes containing walnuts:**
$$\text{Walnuts} = x + 3 = 9 + 3 = 12$$
6. **Calculate the probability:**
$$P(\text{walnuts}) = \frac{\text{number of cupcakes with walnuts}}{\text{total cupcakes}} = \frac{12}{30}$$
Simplify the fraction:
$$\frac{12}{30} = \frac{\cancel{6} \times 2}{\cancel{6} \times 5} = \frac{2}{5}$$
**Final answer:** The probability that a randomly picked cupcake contains walnuts is $\boxed{\frac{2}{5}}$.
Cupcake Walnuts 5955C5
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