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# Help plz (probability)

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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
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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

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