Question

the mean of five positive integers is twice their median. if four of the integers are 3, 4, 5, 9 and median is 6, then the fifth integer.

Answer 1

Median is 6 then Mean = Twice of Median

Mean = 2 * 6 = 12

Sum of all numbers / Count of numbers = Mean

Let the missing number be "X"

So,

(3 + 4 + 5 +9 + X) / 5 = 12

3 + 4 + 5 +9 + X = 12 * 5

X = 60 - 21

X = 39

Therefore missing number i.e. fifth integer is 39