the average age of a family of 6 members is 22 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 ?
"present age of total members = 6 x 22 = 132 7 yrs back their ages were = 6 x 7 = 42 ages at the birth of youngest member = 132 - 42 = 90 therefore , avg age at the birth of youngest member = 90 / 6 = 15 . answer : a"
subtract(divide(subtract(multiply(6, 22), 7), const_4), 7)