Find the DC current gain of a pnp transistor operated in the
     Find the DC current gain of a pnp transistor operated in the active region, if the collector current and emitter current are 12.7 mA, and 12.9 mA respectively. 
  
  Solution
The transistor current in a bipolar NPN transistor is the ratio of these two currents ( Ic/Ib ), called the DC Current Gain of the device and is given the symbol of hfe or nowadays Beta, ( ).
Ie = Ib+Ic
Ic = 12,7mA
Ie = 12.9mA
Ib = Ie-Ic = 12.9-12.7 mA = .2 mA
= 12.7/.2 = 63.5
The DC current gain is 63.5

