Question

Five numbers, x, 2x, 2x + 6, 3x – 1 and 4x – 8, are in a set. If the average (arithmetic mean) of the five numbers is 9, what is the value of the mode in this set?

Answer 1

mode = 8

Explanation:

Find the value of x by using the average formula, that is

`(x+2x+2x+6+3x-1+4x-8)/(5)` = 9

`(12x-3)/(5)` = 9 ( multiply both sides by 5 )

12x - 3 = 45 ( add 3 to both sides )

12x = 48 ( divide both sides by 12 )

x = 4

The set of 5 numbers is

4, 8, 14, 11, 8

The mode is the value in the set which occurs most

mode = 8