To solve these questions, we need to use conditional probability formulas.
(a) To find the probability that a randomly selected individual is 45 to 54 years of age, given the individual is more likely to buy a product emphasized as "Made in our country," we use the formula:
\[ P(A|B) = \frac{P(A \cap B)}{P(B)} \]
where \( A \) is the event that the individual is 45 to 54 years of age, and \( B \) is the event that the individual is more likely to buy the product.
(b) To find the probability that a randomly selected individual is more likely to buy a product emphasized as "Made in our country," given the individual is 45 to 54 years of age, we use the formula:
\[ P(B|A) = \frac{P(A \cap B)}{P(A)} \]
where \( A \) is the event that the individual is 45 to 54 years of age, and \( B \) is the event that the individual is more likely to buy the product.
(c) To determine if 18- to 34-year-olds are more likely to buy a product emphasized as "Made in our country" than individuals in general, we compare the probability of 18- to 34-year-olds being more likely to buy the product to the overall probability of individuals being more likely to buy the product.
To find the probability that a randomly selected individual is 45 to 54 years of age given that the individual is more likely to buy a product emphasized as "Made in our country," we use the formula:
\[
P(45-54 | \text{More likely}) = \frac{P(45-54 \cap \text{More likely})}{P(\text{More likely})}
\]
Substituting the values:
\[
P(45-54 | \text{More likely}) = \frac{396}{1355} \approx 0.2923
\]
Thus, rounded to three decimal places:
\[
P(45-54 | \text{More likely}) \approx 0.292
\]
Next, we find the probability that a randomly selected individual is more likely to buy a product emphasized as "Made in our country," given that the individual is 45 to 54 years of age:
\[
P(\text{More likely} | 45-54) = \frac{P(45-54 \cap \text{More likely})}{P(45-54)}
\]
Substituting the values:
\[
P(\text{More likely} | 45-54) = \frac{396}{603} \approx 0.6567
\]
Thus, rounded to three decimal places:
\[
P(\text{More likely} | 45-54) \approx 0.657
\]
To determine if 18- to 34-year-olds are more likely to buy a product emphasized as "Made in our country" than individuals in general, we compare:
\[
P(\text{More likely} | 18-34) = \frac{217}{520} \approx 0.4173
\]
and
\[
P(\text{More likely}) = \frac{1355}{2217} \approx 0.6112
\]
Since \( 0.4173 < 0.6112 \), we conclude that 18- to 34-year-olds are less likely to buy the product compared to individuals in general.
- \( P(45-54 | \text{More likely}) \approx 0.292 \)
- \( P(\text{More likely} | 45-54) \approx 0.657 \)
- 18- to 34-year-olds are less likely to buy the product.
Thus, the final answer is:
\[
\boxed{\text{No, less likely}}
\]