Answer:
smallest number = 6
Explanation:
given
smallest number = n - 1
middle number = 4(n - 1) = 4n - 4
largest number = 2(4n - 4) = 8n - 8
average is calculated as
average =

here average = 26 and count = 3 , then
= 26 ( multiply both sides by 3 to clear the fraction )
n - 1 + 4n - 4 + 8n - 8 = 78
13n - 13 = 78 ( add 13 to both sides )
13n = 91 ( divide both sides by 13 )
n = 7
then smallest number = n - 1 = 7 - 1 = 6