4 12-sided dice are rolled. What is the probability that the number of dice showing a two digit number is equal to the number of dice showing a one digit number? Express your answer as a common fraction. (Assume that the numbers on the 12 sides are the numbers from 1 to 12 expressed in decimal.)

Creeperhissboom
Apr 17, 2018

#1**+1 **

I'll take a stab at this one.....if the number of dice showing a two-digit number = the number of dice showing a one-digit number, then 2 must show a two-digit number and 2 must show a one-digit number

There are 3 two-digit numbers and 9 one-digit numbers on each die

So....the probabiity is

C(4,2) (3/12)^2 (9/12)^2 =

C(4,2) (1/4)^2 (3/4)^2 =

27/128

CPhill
Apr 17, 2018