Question

lauren is the youngest of four sisters. the average of their ages(all different whole numbers) is 9 years. what is the oldest that lauren can be, in years?

Answer 1

The max of Lauren's age --> the minimum of the others' ages, 1, 2 & 3

4*avg = 4*9 = 36

36 - (1+2+3) = 30

Lauren is 30 yrs of age, or younger.