The Student Room Group

:URGENT: Kindly solve this question asap please!

Two dice rolled once, the probability of obtaining same faces is:
i) 1/6
ii) 0
iii) 5/6
vi) 1/2
v) 1/3
so if you draw a 6 x 6 grid you can tick the relevant boxes where the scores are the same. then work out the probability as a fraction out of 36.
Reply 2
Original post by the bear
so if you draw a 6 x 6 grid you can tick the relevant boxes where the scores are the same. then work out the probability as a fraction out of 36.


Yeah, youre right but considering the fact that this is an MCQ and should take a minute or so to solve, the grid method is gonna take too long. Any shorter method?
Original post by a_09
Yeah, youre right but considering the fact that this is an MCQ and should take a minute or so to solve, the grid method is gonna take too long. Any shorter method?


nah
Reply 4
Original post by a_09
Two dice rolled once, the probability of obtaining same faces is:
i) 1/6
ii) 0
iii) 5/6
vi) 1/2
v) 1/3





Well, two dice have 12 sides in total, and 2 faces will land the same number. so that's 2/12, making it 1/6 if you simplify it by dividing it by 2.

:smile:
Original post by a_09
Yeah, youre right but considering the fact that this is an MCQ and should take a minute or so to solve, the grid method is gonna take too long. Any shorter method?


Yes, though you need to be comfortable with probability.

The two rolls are independent events. This means that for the event "Face X on both" we take the probability of "face X on die 1" and multiply it by the probability of "face X on die 2". Clearly, X=1,2,3,4,5,6 and for each X the probability is 1616=136\frac{1}{6} \cdot \frac{1}{6} = \frac{1}{36}. Since there are 6 possibilities for X, we just multiply 1/36 by 6
Original post by a_09
Yeah, youre right but considering the fact that this is an MCQ and should take a minute or so to solve, the grid method is gonna take too long. Any shorter method?


The poster is not askingyou to do a grid method - there are 36 possible outcomes - how many give a double?
Reply 7
Original post by yasminbh
Well, two dice have 12 sides in total, and 2 faces will land the same number. so that's 2/12, making it 1/6 if you simplify it by dividing it by 2.

:smile:


Yeah. Thank you.
Reply 8
Original post by RDKGames
Yes, though you need to be comfortable with probability.

The two rolls are independent events. This means that for the event "Face X on both" we take the probability of "face X on die 1" and multiply it by the probability of "face X on die 2". Clearly, X=1,2,3,4,5,6 and for each X the probability is 1616=136\frac{1}{6} \cdot \frac{1}{6} = \frac{1}{36}. Since there are 6 possibilities for X, we just multiply 1/36 by 6


Ahan. Thank you!

Quick Reply

Latest