Fine. So i could try to choose a minimal resistor value (for fast turn ON/OFF)and also see that the sink current is also set well within the limit.

Here is were i had the trouble.
For calculating the voltage drops in the resistors for such voltage divider biasing, i used the following formula.,
Drop accross R2 = (Vs*R2)/(R1+R2) => where R1 and R2 are voltage dividing resistors and Vs is the source voltage
and,
for finding the equivalent base resistance(Rb), i used the formula.,
Rb = (R1*R2)/(R1+R2)

But its not giving me the correct result, when i tried to use those formulas in kai's circuit.

Suresh.