Question

How will you join three resistances each of 2 ohm so that the effective resistance is 3 ohm

Answer 1

Nice question!!
Here's your answer!!

It is given that effective resistance is 3 ohms
So 3 = 2 + 1

$1 = \frac{1}{2} + \frac{1}{2}$
So two resistors must be connected in parallel to another resistor in series.
Refer the attachment for connections.

Hope this helps!!
Cheers!!