A parallel combination of two resistors is connected in series with a 4 ohm resistor. If the total effective resistance by these three resistors is 10 ohms then which of the following can be the values of two resistors in parallel connection?

The resistances are added in series. The effective resistance offered by a combination of two resistors in series with a 4 ohms resistor is 10 ohms which means that the equivalent resistance of two resistances in parallel connection must be 6 ohms. Suppose one resistor is "a" ohms and the other resistor is "b" resistors then the equivalent resistance will be \(\frac{\mathrm{ab} }{\mathrm{(a+b)} } = 6\) . Therefore, 8 ohms and 24 ohms resistors will be the correct answer.