I need help with a luckyblock procedure

I am trying to make a luckyblock mod and I need to add the random side of things I use the random block and say if variable is less than 0.1 do this (that works fine), and then I say if variable is greater than 0.9 do this (this also works fine), but then how do I add more things the lucky block can do because I cannot figure out how to say if variable is greater than 0.1 and less than 0.9 do this plz help. Thanks