Solve Question 11 (a) - Mean quantity of palm oil.

Step 1: Solve Question 11 (a) - Mean quantity of palm oil.
The mean ($\bar{x}$) is calculated as the sum of (quantity $\times$ number of families) divided by the total number of families.
The total number of families is $\sum f = 3 + 10 + 4 + 2 + 1 = 20$.
The sum of (quantity $\times$ number of families) is $\sum fx = (0 \times 3) + (1 \times 10) + (2 \times 4) + (3 \times 2) + (4 \times 1)$.

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