Step 1 :\( R_{s1} = R_{1} + R_{2} = 11 + 7 = 18 \)
Step 2 :\( \frac{1}{R_{eq14}} = \frac{1}{R_{4}} + \frac{1}{R_{s1}} = \frac{1}{3} + \frac{1}{18} \)
Step 3 :\( R_{eq14} = \frac{18}{3+1} = \frac{18}{4} = 4.5 \)
Step 4 :\( R_{s2} = R_{eq14} + R_{5} = 4.5 + 9 = 13.5 \)
Step 5 :\( \frac{1}{R_{eq}} = \frac{1}{R_{3}} + \frac{1}{R_{6}} + \frac{1}{R_{s2}} = \frac{1}{19} + \frac{1}{1} + \frac{1}{13.5} \)
Step 6 :\( R_{eq} = \frac{1}{\frac{1}{19} + \frac{1}{1} + \frac{1}{13.5}} \)