total number of years for the 6 pople = 27*6 = 162 years
total number of years for first 4 people = 4*23 = 92 years
total numbers of years for last 3 = 102 years
total number of yeras for last 2 people = 162-92 = 70 years
age of 4th person in line = 102 - 70= 32
