1. Correct. The answer is true.

 

Sample points for the possible sums of the grade points are given in the following table:

 

Second minerals set

1, 6

2, 6

3, 6

4, 6

5, 6

6, 6

1, 5

2, 5

3, 5

4, 5

5, 5

6, 5

1, 4

2, 4

3, 4

4, 4

5,4

6, 4

1, 3

2, 3

3, 3

4, 3

5, 3

6, 3

1, 2

2, 2

3, 2

4, 2

5, 2

6, 2

1, 1

2, 1

3, 1

4, 1

5, 1

6, 1

 

First minerals set

 

Then, the random variable X is given by the sum of the coordinates for each point. Thus for (1,3) we have X=4. Using the fact that all 36 sample points are equally probable, so that each sample point has probability of 1/36, we obtain the following table. For example, corresponding X =4 we have three sample points (1,3), (2,2), (3,1), so that the associated probability is 3/36=1/12.

 

X

2

3

4

5

6

7

8

9

10

11

12

f(x)

1/36

2/36

3/36

4/36

5/36

6/36

5/36

4/36

3/26

2/36

1/36