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MATHEMATICS

JAMB 2023 - Question 2

Mathematics 2023 JAMB Past Questions - Question 2: What is the mean deviation of 3, 5, 8, 11, 12 and 21?

What is the mean deviation of 3, 5, 8, 11, 12 and 21?

A: 3.7

B: 60

C: 4.7

D: 10

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Correct Answer

Explanation

Step 1: Find the mean (average) of the numbers: Mean = (3 + 5 + 8 + 11 + 12 + 21) / 6 Mean = 60 / 6 Mean = 10Step 2: Find the absolute differences between each number and the mean: |3 - 10| = 7 |5 - 10| = 5 |8 - 10| = 2 |11 - 10| = 1 |12 - 10| = 2 |21 - 10| = 11Step 3: Find the mean of those absolute differences: Mean Deviation = (7 + 5 + 2 + 1 + 2 + 11) / 6 Mean Deviation = 28 / 6 Mean Deviation ≈ 4.67So, the mean deviation of the numbers 3, 5, 8, 11, 12, and 21 is approximately 4.7