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Question
The mean of 5, 9, x, 17 and 21 is 13, then find the value of x
Options
9
13
17
21
Solution
13
Explanation;
Hint:
Mean = `(5 + 9 + x + 17 + 21)/5`
13 = `(52 + x)/5`
65 = 52 + x
x = 65 – 52
= 13
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