Probability Question (1 Viewer)

[smithjohn]

A four sided die and a six sided die, numbered 1 to 4 and 1 to 6 respectively are rolled.

• What is the probability of Die 1 greater than or equal to Die 2, given that Die 2 is at least 3.

Please show working

 

[quickoats]

Since this is in the year 9-10 forum, I'm assuming you're in those grades? The method you would use is probably the grid method where you write all the possible combinations and count how many combinations fit the brief (die 1 >= die 2, die 2>=3). Notice how the top row only has 3,4,5,6 as it is given that die 2 is at least 3.

	3	4	5	6
1
2
3	Yes
4	Yes	Yes

Counting the combinations where this is true, and dividing by the total given combinations, we get the probability as 3/16