From the digits 0, 1, 2, 3, three-digit numbers are formed. Among that, the number of even numbers are:
To form a three-digit even number using the digits 0, 1, 2, 3, we must ensure that the last digit is an even number. Here, the even digits available are 0 and 2. Let's explore each case:
For Case 1 (last digit is 0), we select 2 remaining digits from {1, 2, 3} for the first two positions:
For Case 2 (last digit is 2), we select 2 remaining digits from {0, 1, 3} for the first two positions:
Adding both cases gives the total number of even numbers: 6 (Case 1) + 4 (Case 2) = 10.
| Last Digit | Possibilities |
|---|---|
| 0 | 6 |
| 2 | 4 |
| Total | 10 |
Therefore, the number of even numbers that can be formed is 10.
Shown below is an arrangement of closely stacked spheres. Assume each one to be in contact with its immediate neighbour. What is the total number of points where the spheres touch each other?
Eight students (P, Q, R, S, T, U, V, and W) are playing musical chairs. The figure indicates their order of position at the start of the game. They play the game by moving forward in a circle in the clockwise direction.
After the 1st round, the 4th student behind P leaves the game.
After the 2nd round, the 5th student behind Q leaves the game.
After the 3rd round, the 3rd student behind V leaves the game.
After the 4th round, the 4th student behind U leaves the game.
Who all are left in the game after the 4th round?

Shown on the left is a set of equations. Which option belongs to the same set? 
What is 'X' in the following table?