1. The problem statement, all variables and given/known data Pritesh is taller than Davina who is taller than Alicia. The difference in height between Pritesh and Davina is the same as the difference in height between Davina and Alicia. The total of their heights is 300 cm. How tall is Davina? 2. Relevant equations Now trial and error gives me Alicia = 50cm, Davina = 100cm and Pritesh = 150cm as the difference between them is 50cm 3. The attempt at a solution How could I do this problem using only algebra, rather than what I did with trial and error?