relay resistance

[paulb89]

Hi can anyone help me solve this question and explain how they got the answer?

Cheers

 

[ADRT]

https://www.kitronik.co.uk/blog/how-to-calculate-resistors-in-series-and-parallel/

 

[paulb89]

Thank you ! Most appreciated

 

[jedro]

Think about if first for a second. A given is the 275 ohms across the contacts of the relay.

If you add another path for current to flow then it should be intuitive that the total resistance will drop. That is, it will be less.

Of the four answers provided, one is the given resistance, one is lower than the given resistance and the other two are more than the given resistance.

So with this known, which is the correct answer of the four?

But now if there were two answers that were less than the given resistance you would have to do the math.