Use multiplication:
2842 x 11:
Line up our numbers vertically:
2 | 8 | 4 | 2 | |
x | 1 | 1 |
Current result: 1 x 2 = 2
2 | 8 | 4 | 2 | ||||
x | 1 | 1 | |||||
2 |
Show value = 2
Current result: 1 x 4 = 4
2 | 8 | 4 | 2 | ||||
x | 1 | 1 | |||||
4 | 2 |
Show value = 4
Current result: 1 x 8 = 8
2 | 8 | 4 | 2 | ||||
x | 1 | 1 | |||||
8 | 4 | 2 |
Show value = 8
Current result: 1 x 2 = 2
2 | 8 | 4 | 2 | ||||
x | 1 | 1 | |||||
2 | 8 | 4 | 2 |
Show value = 2
New multiplication row:
Insert a 0 as our placeholder
Current result: 1 x 2 = 2
2 | 8 | 4 | 2 | ||||
x | 1 | 1 | |||||
2 | 8 | 4 | 2 | ||||
2 | 0 |
Show value = 2
Current result: 1 x 4 = 4
2 | 8 | 4 | 2 | ||||
x | 1 | 1 | |||||
2 | 8 | 4 | 2 | ||||
4 | 2 | 0 |
Show value = 4
Current result: 1 x 8 = 8
2 | 8 | 4 | 2 | ||||
x | 1 | 1 | |||||
2 | 8 | 4 | 2 | ||||
8 | 4 | 2 | 0 |
Show value = 8
Current result: 1 x 2 = 2
2 | 8 | 4 | 2 | ||||
x | 1 | 1 | |||||
2 | 8 | 4 | 2 | ||||
2 | 8 | 4 | 2 | 0 |
Show value = 2
Add up our results by column:
2 | 8 | 4 | 2 | ||||
x | 1 | 1 | |||||
2 | 8 | 4 | 2 | ||||
2 | 8 | 4 | 2 | 0 | |||
2 |
Adding up column 1, we get: 2 + 0
Our column sum becomes 2.
2 | 8 | 4 | 2 | ||||
x | 1 | 1 | |||||
2 | 8 | 4 | 2 | ||||
2 | 8 | 4 | 2 | 0 | |||
6 | 2 |
Adding up column 2, we get: 4 + 2
Our column sum becomes 6.
2 | 8 | 4 | 2 | ||||
x | 1 | 1 | |||||
2 | 8 | 4 | 2 | ||||
2 | 8 | 4 | 2 | 0 | |||
2 | 6 | 2 |
Adding up column 3, we get: 8 + 4
Our column sum becomes 12.
Since our sum is greater than 9, we will carry a 1 over for the next column sum.
2 | 8 | 4 | 2 | ||||
x | 1 | 1 | |||||
2 | 8 | 4 | 2 | ||||
2 | 8 | 4 | 2 | 0 | |||
1 | 2 | 6 | 2 |
Adding up column 4, we get: 2 + 8
Add carry value 1 to this column sum to get 11.
Since our sum is greater than 9, we will carry a 1 over for the next column sum.
2 | 8 | 4 | 2 | ||||
x | 1 | 1 | |||||
2 | 8 | 4 | 2 | ||||
2 | 8 | 4 | 2 | 0 | |||
3 | 1 | 2 | 6 | 2 |
Adding up column 5, we get: 2
Add carry value 1 to this column sum to get 3.