Two resistors of resistance $4\, \Omega$ and $6\, \Omega$ are connected in parallel to a cell to draw 0.5 A current from the cell. What is current through resistor $4\, \Omega$ ?

Here, R1=4 ohm ,

R2= 6 ohm .

I= 0.5A.

using current divider rule,

In a parallel resistance system current in 1st branch $=I_{1}=\left(\frac{R_{2}}{R_{1}+R_{2}}\right) \times I, I_{1}=\frac{6}{4+6} \times 0.5, I_{1}=\frac{3}{10}=0.3 \mathrm{~A}$