Answer:
x = [tex]\frac{1}{3}[/tex]
Step-by-step explanation:
[tex]\frac{1}{x} + \frac{1}{3x} = 4[/tex] (Multiply everything by LCM)
[tex]3x*\frac{1}{x} + 3x*\frac{1}{3x}=3x*4[/tex] (Simplify the fractions)
[tex]3+1=12x\\4=12x\\x=4/12\\x=\frac{1}{3}[/tex]
