oK here it is! Three identical resistors are connected in parallel. The equivalent resistance increases by 700 ohms when one resistor is removed and connected in series with the remaining two, which are still in parallel. Find the resistance of each resistor. Ok my thoughts: Ok in situation one, we have: 1/Req=1/R1+1/R2+1/R3. In situation two we have: 1/Req +700 ohm=(R1+R2)+1/R3, R1+R2=Reff. So 1/Req +700 ohm=1/Reff+1/R3. Ok, now I'm stuck...Any tips welcome!