A student has two test marks, 6 with weight 2 and 8 with weight 3. What is the weighted mean?
Answer and explanation
Correct answer: B. 7.2
- Step 1: Weighted sum = 6 x 2 + 8 x 3 = 12 + 24 = 36. Step 2. Divide by the total weight 5: 36 / 5 = 7.2. Answer: 7.2. Why not the others: A simple mean ignores weights; swapping weights gives 6.8, not 7.5.
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