SOLUTION: Erin has an older sister and a younger sister. Her older sister is one year more than twice Erin's younger sister is three years younger than she is. The sum of their ages is 26. F

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons  -> Quadratic Equation Lesson -> SOLUTION: Erin has an older sister and a younger sister. Her older sister is one year more than twice Erin's younger sister is three years younger than she is. The sum of their ages is 26. F      Log On


   

Question 876401: Erin has an older sister and a younger sister. Her older sister is one year more than twice Erin's younger sister is three years younger than she is. The sum of their ages is 26. Find Erin's age
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
(2E + 1) + E + (E-3) = 26
4E= 28
E = 7, Erin's age. Older sister is 15, Younger sister is 4
and...15 + 7 + 4 = 26