Answer:
Option B
Step-by-step explanation:
In this question , we just need to make "F" as the subject of the equation.
So, lets solve the equation.
[tex]R = \frac{F}{N + F}[/tex]
→ Multiplying (N + F) on both the sides ,
[tex]=> R \times (N + F) = \frac{F}{(N + F)} \times (N + F)[/tex]
[tex]=> RN + RF = F[/tex]
→ Substracting both the sides with RF ,
[tex]=> RN + RF - RF = F - RF[/tex]
[tex]=> RN = F - RF[/tex]
→ Taking F common from R.H.S ,
[tex]=> RN = F(1 - R)[/tex]
→ Dividing both the sides by (1 - R) ,
[tex]=> \frac{RN}{1 - R} = \frac{F(1 - R)}{(1 - R)}[/tex]
[tex]=> \frac{RN}{1 - R} = F[/tex]
∴ Hence , [tex]F = \frac{RN}{1 - R}[/tex]
