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Question
The mean of five positive integers is twice their median. If four of the integers are 3, 4, 6, 9 and median is 6, then find the fifth integer
Solution
Let the 5th positive integer be x
`bar(x) = (3 + 4 + 6 + 9 + x)/5`
= `(22 + x)/5`
Median = 6
Mean = 2 × median
`(22 + x)/5` = 2 × 6
22 + x = 60
x = 60 – 22
= 38
The fifth integer is 38.
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