Question

if three resistors of 6 ohm 9 ohm and 21 ohm are connected in series to a 21 v battery find the total resistance of the circuit. the current flowing through the circuit. the potential difference across the 21 ohm resistor

Answer 1

6+9+21=36ohm=R
and v=21v
then I=v/R
I=21/36=7/12

Answer 2

$36 \: ohm \: total \\ current \: = 21 \div 36 \times 21 = 49 \div 4 = 12.25$