Microwave Engineering -- Noise figure of a cascade

[peripatein]

Hi,
I am taking a course in Microwave Engineering and we were given the following problem to solve
An amplifier with a gain of 12 dB, a bandwidth of 150 MHz, and a noise figure of 4 dB feeds a
receiver with a noise temperature of 900 K. Find the noise figure of the overall system.
Need I to use the following relation?:
Fcas=F1 + (F2-1)/G = F1 + (T/T0)/G? Where T=900 K and T0=290 K.
I'd appreciate some guidance.

 

[rude man]

You don't need any guidance since you got it right the 1st time! (assuming your G = 10^1.2).