[tex] C = \dfrac{100w}{L} [/tex]
w is on the right side multiplied by 100/L.
[tex] C = \dfrac{100}{L} \times w [/tex]
Now multiply both sides by the reciprocal of 100/L,
which is L/100, to isolate w.
[tex] C \times \dfrac{L}{100} = \dfrac{L}{100} \times \dfrac{100}{L} \times w [/tex]
[tex] \dfrac{CL}{100} = w [/tex]
[tex] w = \dfrac{CL}{100} [/tex]
[tex] w = \dfrac{LC}{100} [/tex]
Answer: choice B.