What is the probability that rolling two identical dice together will

Question

What is the probability that rolling two identical dice together will result in the sum of the dice adding to 7?

A. 1/36
B. 1/6
C. 1/3
D. 5/6
E. 35/36

Sasindran · Answer

B.

sample set = 36.

1,1 1,2 1,3 1,4 1,5 1,6
2,1 2,2 2,3 2,4 2,5 2,6
3,1 3,2 3,3 3,4 3,5 3,6
4,1 4,2 4,3 4,4 4,5 4,6
5,1 5,2 5,3 5,4 5,5 5,6
6,1 6,2 6,3 6,4 6,5 6,6

no of sum of 7 from first row=1
no of sum of 7 from second row=1
no of sum of 7 from third row=1
no of sum of 7 from fourth row=1
no of sum of 7 from fifth row=1
no of sum of 7 from sixth row=1

Total=6

Probability = 6/36 = 1/6

mamun2871 · Answer

Total no. of outcomes 6*6=36.
Possible outcomes are (6,1),(1,6),(5,2),(2,5),(4,3),(3,4)= 6
Hence, Probability=6/36=1/6

JeffTargetTestPrep · Answer

With 2 six-sided dice, there are 6 x 6 = 36 total outcomes from a roll of both dice.

Of those 36 outcomes, the ones that sum to 7 are:

1,6 and 6,1

2,5 and 5,2

3,4 and 4,3

Thus, the probability is 6/36 = 1/6.

Answer: B

kesanmanish · Answer

JeffTargetTestPrep  - Ain't both dices are identical . So (1,2) and (2,1) would be same and hence total sample space would be 21 instead of 36. Where am i wrong?

BrushMyQuant · Answer

We need to find What is the probability that rolling two identical dice together will result in the sum of the dice adding to 7?

As we are rolling two dice => Number of cases =  6^2  = 36

Lets start listing down the cases where the sum of the two numbers is 7. Following are the possible cases
(1,6)
(2,5)
(3,4)
(4,3)
(5,2)
(6,1)

=> 6 cases

=> Probability that rolling two identical dice together will result in the sum of the dice adding to 7 =  \frac{6}{36}  =  \frac{1}{6}

So,  Answer will be B 
Hope it helps!

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