1. Problem: Find the average of given sets of numbers. 2. Recall: The average of $n$ numbers $x_1, x_2, ..., x_n$ is calculated using the formula: $$\text{Average} = \frac{x_1 + x_2 + ... + x_n}{n}$$ 3. Solution: a. Numbers: 3, 5, 7, 4, 11 Sum = $3 + 5 + 7 + 4 + 11 = 30$ Count = 5 Average = $\frac{30}{5} = 6$ b. Numbers: 12, 15, 11, 14, 13, 7 Sum = $12 + 15 + 11 + 14 + 13 + 7 = 72$ Count = 6 Average = $\frac{72}{6} = 12$ c. Numbers: 10, 12, 15, 11 (Rs ignored for average calculation) Sum = $10 + 12 + 15 + 11 = 48$ Count = 4 Average = $\frac{48}{4} = 12$ d. Numbers: 3, 7, 9, 6, 2, 8, 7 (meters units ignored for average calculation) Sum = $3 + 7 + 9 + 6 + 2 + 8 + 7 = 42$ Count = 7 Average = $\frac{42}{7} = 6$ e. Numbers: 9, 11, 13, 15 (Kg units ignored for average calculation) Sum = $9 + 11 + 13 + 15 = 48$ Count = 4 Average = $\frac{48}{4} = 12$ f. Numbers: 6, 8, 10, 12, 14 (litres units ignored for average calculation) Sum = $6 + 8 + 10 + 12 + 14 = 50$ Count = 5 Average = $\frac{50}{5} = 10$ g. Numbers: 28, 31, 35, 39, 37, 41, 40 (°c units ignored for average calculation) Sum = $28 + 31 + 35 + 39 + 37 + 41 + 40 = 251$ Count = 7 Average = $\frac{251}{7} \approx 35.86$ 4. Word problem example: Weight of parcels: 11.8kg, 13.4kg, 12.1kg, 14.7kg, 13.5kg, 12.8kg Sum = $11.8 + 13.4 + 12.1 + 14.7 + 13.5 + 12.8 = 78.3$ Count = 6 Average weight = $\frac{78.3}{6} = 13.05$ kg Final answers: a. 6 b. 12 c. 12 d. 6 e. 12 f. 10 g. 35.86 Word problem average weight: 13.05 kg