Multiplication by 11, step by step
The elevens are the friendliest table to look at: for the first nine facts, you just write the digit twice.
The question
11 × 11
11×11
11 × 11=11 × 11
11 × 5=55
11 × 6=66
55+66=121
11×11=121
- 11 × 11 means 11 groups with 11 in each one — 11 rows of 11. The answer counts everything in all of them, not one row.
- Added up, that is 11 written 11 times — nobody wants to do that. Turn it round: 11 × 11 is the same amount, and it is only 11 lots of 11 to add instead.
- If 11 × 11 will not come, split the 11 at five: 11 × 5 = 55, and 11 × 6 = 66. Together that is 55 + 66 = 121.
- So 11 × 11 = 121.
How it works.
- 01
11 × 11 means 11 groups with 11 in each one — 11 rows of 11. The answer counts everything in all of them, not one row.
- 02
Added up, that is 11 written 11 times — nobody wants to do that. Turn it round: 11 × 11 is the same amount, and it is only 11 lots of 11 to add instead.
- 03
If 11 × 11 will not come, split the 11 at five: 11 × 5 = 55, and 11 × 6 = 66. Together that is 55 + 66 = 121.
- 04
So 11 × 11 = 121.