Use multiplication:
987 x 654:
Line up our numbers vertically:
| 9 | 8 | 7 | |
| x | 6 | 5 | 4 |
Current result: 4 x 7 = 28
| 9 | 8 | 7 | |||||
| x | 6 | 5 | 4 | ||||
| 8 |
Show value = 8
Carry value = 2
Step 2:
Last step carry value was 2.
Our current result equals:
4 x 8 + Carry value of 2 = 34
| 2 | |||||||
| 9 | 8 | 7 | |||||
| x | 6 | 5 | 4 | ||||
| 4 | 8 |
Show value = 4
Carry value = 3
Step 3:
Last step carry value was 3.
Our current result equals:
4 x 9 + Carry value of 3 = 39
| 3 | 2 | ||||||
| 9 | 8 | 7 | |||||
| x | 6 | 5 | 4 | ||||
| 3 | 9 | 4 | 8 |
Show value = 39
New multiplication row:
Insert a 0 as our placeholder
Current result: 5 x 7 = 35
| 9 | 8 | 7 | |||||
| x | 6 | 5 | 4 | ||||
| 3 | 9 | 4 | 8 | ||||
| 5 | 0 |
Show value = 5
Carry value = 3
Step 5:
Last step carry value was 3.
Our current result equals:
5 x 8 + Carry value of 3 = 43
| 3 | |||||||
| 9 | 8 | 7 | |||||
| x | 6 | 5 | 4 | ||||
| 3 | 9 | 4 | 8 | ||||
| 3 | 5 | 0 |
Show value = 3
Carry value = 4
Step 6:
Last step carry value was 4.
Our current result equals:
5 x 9 + Carry value of 4 = 49
| 4 | 3 | ||||||
| 9 | 8 | 7 | |||||
| x | 6 | 5 | 4 | ||||
| 3 | 9 | 4 | 8 | ||||
| 4 | 9 | 3 | 5 | 0 |
Show value = 49
New multiplication row:
Insert a 00 as our placeholder
Current result: 6 x 7 = 42
| 9 | 8 | 7 | |||||
| x | 6 | 5 | 4 | ||||
| 3 | 9 | 4 | 8 | ||||
| 4 | 9 | 3 | 5 | 0 | |||
| 2 | 0 | 0 |
Show value = 2
Carry value = 4
Step 8:
Last step carry value was 4.
Our current result equals:
6 x 8 + Carry value of 4 = 52
| 4 | |||||||
| 9 | 8 | 7 | |||||
| x | 6 | 5 | 4 | ||||
| 3 | 9 | 4 | 8 | ||||
| 4 | 9 | 3 | 5 | 0 | |||
| 2 | 2 | 0 | 0 |
Show value = 2
Carry value = 5
Step 9:
Last step carry value was 5.
Our current result equals:
6 x 9 + Carry value of 5 = 59
| 5 | 4 | ||||||
| 9 | 8 | 7 | |||||
| x | 6 | 5 | 4 | ||||
| 3 | 9 | 4 | 8 | ||||
| 4 | 9 | 3 | 5 | 0 | |||
| 5 | 9 | 2 | 2 | 0 | 0 |
Show value = 59
FINAL ADDITION SECTION
Add up our results by column:
| 9 | 8 | 7 | |||||
| x | 6 | 5 | 4 | ||||
| 3 | 9 | 4 | 8 | ||||
| 4 | 9 | 3 | 5 | 0 | |||
| 5 | 9 | 2 | 2 | 0 | 0 | ||
| 8 |
Adding up column 1, we get: 8 + 0 + 0
Our column sum becomes 8.
| 9 | 8 | 7 | |||||
| x | 6 | 5 | 4 | ||||
| 3 | 9 | 4 | 8 | ||||
| 4 | 9 | 3 | 5 | 0 | |||
| 5 | 9 | 2 | 2 | 0 | 0 | ||
| 9 | 8 |
Adding up column 2, we get: 4 + 5 + 0
Our column sum becomes 9.
| 9 | 8 | 7 | |||||
| x | 6 | 5 | 4 | ||||
| 3 | 9 | 4 | 8 | ||||
| 4 | 9 | 3 | 5 | 0 | |||
| 5 | 9 | 2 | 2 | 0 | 0 | ||
| 4 | 9 | 8 |
Adding up column 3, we get: 9 + 3 + 2
Our column sum becomes 14.
Since our sum is greater than 9, we will carry a 1 over for the next column sum.
| 9 | 8 | 7 | |||||
| x | 6 | 5 | 4 | ||||
| 3 | 9 | 4 | 8 | ||||
| 4 | 9 | 3 | 5 | 0 | |||
| 5 | 9 | 2 | 2 | 0 | 0 | ||
| 5 | 4 | 9 | 8 |
Adding up column 4, we get: 3 + 9 + 2
Add carry value 1 to this column sum to get 15.
Since our sum is greater than 9, we will carry a 1 over for the next column sum.
| 9 | 8 | 7 | |||||
| x | 6 | 5 | 4 | ||||
| 3 | 9 | 4 | 8 | ||||
| 4 | 9 | 3 | 5 | 0 | |||
| 5 | 9 | 2 | 2 | 0 | 0 | ||
| 4 | 5 | 4 | 9 | 8 |
Adding up column 5, we get: 4 + 9
Add carry value 1 to this column sum to get 14.
Since our sum is greater than 9, we will carry a 1 over for the next column sum.
| 9 | 8 | 7 | |||||
| x | 6 | 5 | 4 | ||||
| 3 | 9 | 4 | 8 | ||||
| 4 | 9 | 3 | 5 | 0 | |||
| 5 | 9 | 2 | 2 | 0 | 0 | ||
| 6 | 4 | 5 | 4 | 9 | 8 |
Adding up column 6, we get: 5
Add carry value 1 to this column sum to get 6.
