Question

what resistance must be placed in series with a 35 ohm resistor to make the total of 12 ohm?

Answer 1

I think there is some ambiguity with the question.....

Problem asks to connect resistance in "series" with 35 ohm resistor to make total of 12 ohm which is not possible....

However, equivalent resistance in series = R1 + R2 = 35 + (something) , which can't be less than 35 i.e (12 ohm).....

...it has to be parallel connection....

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