# Need a bit of guidance in regards to this PNP transistor question

simulate this circuit – Schematic created using CircuitLab

Hello!

I'm currently stuck trying to answer this question. The question asks for me to find the resistance of R2 for R1 to be at 4V when the PNP transistor has a beta of 250. My current train of thought was to substitute 4V as the voltage of R1 and solve for current which gave me 80mA, then use Ic = β/Ib to calculate Ib which was 0.32mA. I also worked the emitter current, Ie to be approximately 79mA.

This is where I got stuck, I now know the current of R2 but I don't know the voltage or the resistance so I can't work out either of these values. Is there something I'm not considering here? Am I going about this the wrong way? I'm really confused. Any help would be appreciated!

• Was the VBE given to you? If not, are you told the saturation current for the BJT? – jonk Apr 24 '18 at 23:22