Cool, I just saboed myself rite in front of my student with this physics question I gave to him on the spot. I ended up not knowing the answer and had to go back home to ask around. *Malu!!* Here comes the fun part...no one knows the answer either!! Well done vickz for coming up with a top notch question for an 'O' level student...

*so, does anyone knows the effective total resistance of this circuit? the vales of resistors are as given in the pic*