Answer:
D. 5/3
Step-by-step explanation:
[tex]\frac{1/6+1/2+1/3+x}{4} =2/3[/tex]
[tex]1/6+1/2+1/3+x=8/3[/tex]
[tex]x=8/3-1/6-1/2-1/3[/tex]
[tex]x=8/3-1/6-3/6-2/6[/tex]
[tex]x=8/3-6/6[/tex]
[tex]x=16/6-6/6=10/6[/tex]
simplified
[tex]x=5/3[/tex]
Hope this helps