Question

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Explanation:

Step1: Calculate total survey respondents

Add all values from the Venn diagram:
$84 + 17 + 25 + 15 = 141$

Step2: Find value of $a$

$a$ is the relative frequency of people who like neither (15 people):
$\frac{15}{141} \times 100\% \approx 11\% \approx 12\%$

Step3: Find value of $b$

$b$ is the relative frequency of people who like turnips only (25 people):
$\frac{25}{141} \times 100\% \approx 17.7\% \approx 18\%$

Answer:

a = 12%, b = 18%