Answer:
13 years old
Step-by-step explanation:
Let the age now be = [tex]x[/tex]
Age 5 years ago = [tex]x - 5[/tex]
Age 11 years from now = [tex]x + 11[/tex]
[tex]x - 5 = \frac{1}{3}(x+11)[/tex]
[tex]x - 5 = \frac{1}{3}x + \frac{11}{3}[/tex]
[tex]x - \frac{1}{3}x = \frac{11}{3} + 5[/tex]
[tex]\frac{2}{3}x = \frac{26}{3}[/tex]
[tex]x = \frac{26}{3}/\frac{2}{3}[/tex]
[tex]x = 13[/tex]
