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You are given a fair six-sided dice with the numbers 1 – 6 on the 6 sides.  You roll the dice six times.  What is the probability of rolling a 5 or 6 at least 5 times?  Round your answer to 2 decimal places.

 Jul 9, 2019
edited by adawertfswert  Jul 9, 2019
 #1
avatar+103999 
+2

P(5 or 6)  =  2/6  = 1/3

 

P ( rolling 5 or 6  five times )  =  C(6, 5) (1/3)^5 (2/3)

 

P( roling 5 or 6 six times)  =  (1/3)^6

 

So....the combined probability is

 

C(6,5) (1/3)^5 (2/3) + (1/3)^6   =  13 / 729  ≈ .02

 

 

cool cool cool

 Jul 9, 2019
 #2
avatar
0

I don't get why we multiply by 2/3. Could someone explain

 Jul 10, 2019
edited by Guest  Jul 10, 2019
edited by Guest  Jul 10, 2019
edited by Guest  Jul 10, 2019
 #3
avatar+1338 
0

the number 5 to 6 are 2 numbers out of 6...

 

therefore, 1/3. 

 

1- 1/3=2/3

tommarvoloriddle  Jul 10, 2019
 #4
avatar+1750 
0

This is not the correct reason, Tom! 

GA

GingerAle  Jul 10, 2019
edited by GingerAle  Jul 10, 2019
 #5
avatar+1338 
0

how would you do it, Ginger/GA/Ginger Ale/GingerA/more stuff?

tommarvoloriddle  Jul 10, 2019
 #6
avatar+791 
+4

Tom is right

 

Travisio

 Jul 10, 2019
 #7
avatar+1338 
+1

Wut? I think I am wrong... 

 

\(tommarvoloriddle\)

tommarvoloriddle  Jul 11, 2019
 #8
avatar+791 
+4

Well thats the only solution I can think of \(riddle\)

 

Travisio

travisio  Jul 11, 2019

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