Present age of total members = 6 X 28 = 168
7 yrs back their ages were = 6 x 7 = 42
Ages at the birth of youngest member = 168 - 42 = 126
Therefore, avg age at the birth of youngest member = 126/6 = 21.
The average age of a family of 6 members is 28 years.If the age of the youngest member is 7 years,what was the average age of the family at the birth of the youngest member?
* 15
* 18
* 21
* 12
* 19