The last digit of any multiplication depends only on the last digit of each number being multiplied, and not for example, on the size of the numbers or their order.
\[3 \times 2=6\]
If the last digit of a number is 2 and the last digit of any other number is 3, the last digit of their multiple will be 6, so the last digit of
\[53 \times 42=2226\]
is 6. The complete list of posdible combinations of last digits is given in the table.
Number A\Number B | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 |
0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
1 | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 |
2 | 0 | 2 | 4 | 6 | 8 | 0 | 2 | 4 | 6 | 8 |
3 | 0 | 3 | 6 | 9 | 2 | 5 | 8 | 1 | 4 | 7 |
4 | 0 | 4 | 8 | 2 | 6 | 0 | 4 | 8 | 2 | 6 |
5 | 0 | 5 | 0 | 5 | 0 | 5 | 0 | 5 | 0 | 5 |
6 | 0 | 6 | 2 | 8 | 4 | 0 | 6 | 2 | 8 | 4 |
7 | 0 | 7 | 4 | 1 | 8 | 5 | 2 | 9 | 6 | 3 |
8 | 0 | 8 | 6 | 4 | 2 | 0 | 8 | 6 | 4 | 2 |
9 | 0 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 |