Explanation:

- We know the average of X, Y, and Z is 2X. This can be written as:

(X + Y + Z) / 3 = 2X

So, X + Y + Z = 6X.

- We also know the average of Y and Z is 20, which means:

(Y + Z) / 2 = 20

So, Y + Z = 40.

- Now substitute Y + Z = 40 in the first equation:

X + 40 = 6X

40 = 6X - X

40 = 5X

X = 8

- Considering the options:

Option 1: 6

Option 2: 8

Option 3: 10

Option 4: 5

- The correct answer is Option 2: 8.