Let us learn here how to use resistor as voltage divider. It is a passive linear circuit which gives fraction of voltage of the input side.
We can simply say that voltage divider divides the input voltage (Vin) in a specific network of two resistors connected in series. These two resistors are connected in series, then input voltage (Vi) is given across these resistor pairs. And finally output (Vo) is taken from junction of the two resistors.
The dedicated circuit and formula to calculate parameters in the circuit is as below :