A pair of fair six-sided dice is rolled. If at least one of the dice

Question

A pair of fair six-sided dice is rolled. If at least one of the dice is a 1. What is the probability that both dice are showing a 1?

A. 1/12 
B. 1/11
C. 1/10
D. 1/6
E. 1/2

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Babineaux · Answer

Already given at least one of the dice is at 1.

Then the answer lies within other dice, when it will be at 1 the event will be satisfied.

Thus for both the dices at 1, the probability will be 1/6.

IMO ans is D.

shameekv1989 · Answer

1_ or _1 or 11

_ can take 5 values

Total ways = 5+5+1 = 11

Therefore probability of 1,1 on two dices will be 1/11

Answer - B

AnirudhaS · Answer

The trick to the problem is realising that the event (1,1) is ONE event. 
(1,1) --> Same event
(1,2)
(1,3)
(1,4)
(1,5)
(1,6)

(1,1) --> Same event
(2,1)
(3,1)
(4,1)
(5,1)
(6,1)

Total no. of possible events = 11
One occurs in both the throws = 1 way
Required probability =  \frac{1}{11}

Answer:  B

sambitspm · Answer

There are 3 cases (first dice, second dice) => (1,x) , (1,1) , (x,1). x!=1
Total Probability = 1/6 * 5/6 + 1/6+1/6 + 5/6*1/6
Favourable Probability = 1/6*1/6

Answer = 1/(5+1+5)= 1/11
IMO B

Regor60 · Answer

If only one die shows a 1, then the other die can show 5 other numbers and satisfy the condition, for 5 ways.

But, since there are two dice, there are 2*5 = 10 ways for one die to show a 1.

"At least one" means one or more. "Or" means add. So, two dice showing 1 also satisfies the question and of course can happen only

1 way

So, 10+1 = 11 ways to meet the condition. But, only 1 case where both dice show 1, so the probability is

1/11

Posted from my mobile device

bumpbot · Answer

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A pair of fair six-sided dice is rolled. If at least one of the dice

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A pair of fair six-sided dice is rolled. If at least one of the dice

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