A six-sided die with faces numbered one through six is rolled twice.

Question

A six-sided die with faces numbered one through six is rolled twice. What is the probability that the face with the number 2 on it will not be facing upward on either roll?

A. 1/6 
B. 2/3 
C. 25/36 
D. 17/18 
E. 35/36

saukrit · Answer

Probability of not getting a 2 on the first roll =5/6
Probability of not getting a 2 on the second roll =5/6

Probability of not getting 2 in either turn = 5/6 * 5/6 = 25/36

IMO, Answer is C

Archit3110 · Answer

P ( not getting 2 ) 1st roll; 5/6 and 2nd roll; 5/6
IMO 5/6*5/6 ; 25/36
IMO C

sach24x7 · Answer

Probability of not getting 2 means getting any number other than 2....so the probability would be 5 numbers out of 6

5/6 * 5/6 = 25/36

btrg · Answer

can we do like this ----> 2 comes on both rolls i.e 1/6 * 1/6= 1/36

then substract this from 1 i.e 35/36.

sach24x7 · Answer

You will have to add two more probabilities for 2 on first roll and 2 on second roll and then minus it from 1

Posted from my mobile device

philipssonicare · Answer

Two ways to approach this:
 1) Probability that a 2 it is not face up, 'P' 
 \frac{5}{6}*\frac{5}{6}=\frac{25}{36}

Straight forward

2) 1- Probability that a 2 is face up '1-P' 
Probability two 2s
 \frac{1}{6}*\frac{1}{6}=\frac{1}{36}

Probability 2 on the first die but not on the second
 \frac{1}{6}*\frac{5}{6}=\frac{5}{36}

Probability 2 on the second die but not on the first
 \frac{5}{6}*\frac{1}{6}=\frac{5}{36}

Sum these probabilities together:  \frac{1}{36}+\frac{5}{36}+\frac{5}{36}=\frac{11}{36}

1-\frac{11}{36}=\frac{25}{36}

bumpbot · Answer

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A six-sided die with faces numbered one through six is rolled twice.

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A six-sided die with faces numbered one through six is rolled twice.

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