CAYLEY 2019 Problem 10

Matilda and Ellie divide a white wall in their bedroom in half, each taking half of the wall. Matilda paints half of her section red. Ellie paints one third of her section red. The fraction of the entire wall that is painted red is

Answer Choices
A. \frac{5}{12}
B. \frac{2}{5}
C. \frac{2}{3}
D. \frac{1}{6}
E. \frac{1}{2}