Question

John rolls a six-sided number cube twice. What is the probability of getting an even number and then an odd number?

5/6
1/4
1/2
1/6

Answer 1

Option 2 -
`\text{Probability}=(1)/(4)`

Explanation:

Given : John rolls a six-sided number cube twice.

To find : What is the probability of getting an even number and then an odd number?

Solution :

When rolls a six-sided number cube twice

(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)

Now,

`\text{Probability}=\frac{\text{Favorable outcome}}{\text{Total number of outcome}}`

Favorable outcome of getting an even number and then an odd number:

(2,1) (2,3) (2,5) (4,1) (4,3) (4,5) (6,1) (6,3) (6,5)

So, Favorable outcome = 9

Total number of outcome = 36

`\text{Probability}=(9)/(36)`

`\text{Probability}=(1)/(4)`

Therefore, Option 2 is correct.