sum_(c=1)^3 sum_(b=0)^2 3!/(b!*c!*(3-b-c)!)*0.2^c*0.3^b*0.4^(3-b-c)

Uh oh! Wolfram|Alpha doesn't run without JavaScript.

Please enable JavaScript. If you don't know how, you can find instructionshere.Once you've done that, refresh this page to start using Wolfram|Alpha.