21 Times (21×) Multiplication Table
21 times table, 1 to 20
| 21 × 1 | 21 |
| 21 × 2 | 42 |
| 21 × 3 | 63 |
| 21 × 4 | 84 |
| 21 × 5 | 105 |
| 21 × 6 | 126 |
| 21 × 7 | 147 |
| 21 × 8 | 168 |
| 21 × 9 | 189 |
| 21 × 10 | 210 |
| 21 × 11 | 231 |
| 21 × 12 | 252 |
| 21 × 13 | 273 |
| 21 × 14 | 294 |
| 21 × 15 | 315 |
| 21 × 16 | 336 |
| 21 × 17 | 357 |
| 21 × 18 | 378 |
| 21 × 19 | 399 |
| 21 × 20 | 420 |
Patterns that help you remember it
- The last digits repeat in a cycle of 10: 1, 2, 3, 4, 5, 6, 7, 8, 9, 0.
- Split it into tens and ones: 21 × k = 20 × k + 1 × k.
- Each answer is 21 more than the one before, so you can count on in steps of 21.
Building it from tables you already know
To multiply 21 by 9, multiply by 10 and take one 21 away: 210 − 21 = 189. To multiply by 11, multiply by 10 and add one more 21: 210 + 21 = 231. Multiplying by 4 is doubling twice: 21 → 42 → 84.
There are 4 multiples of 21 below 100, and 47 below 1,000. A number is in the 21 times table exactly when it divides by 21 with no remainder.
Odd, even and the last digit
Because 21 is odd, the answers alternate between odd and even: 21 × 1 = 21 is odd, 21 × 2 = 42 is even, and so on. Multiplying by 10 always puts a zero on the end: 21 × 10 = 210, and 21 × 100 = 2,100. Multiplying by 5 is half of multiplying by 10: half of 210 is 105.
Using the 21 times table to divide
Every fact also works backwards: because 21 × 7 = 147, you know 147 ÷ 21 = 7 and 147 ÷ 7 = 21. Practising the table and its division facts together halves the work.
21 times table practice worksheet
- 21 × 2 = ______
- 21 × 6 = ______
- 21 × 10 = ______
- 21 × 9 = ______
- 21 × 1 = ______
- 21 × 7 = ______
- 21 × 6 = ______
- 21 × 11 = ______
- 21 × 9 = ______
- 21 × 3 = ______
- 21 × 8 = ______
- 21 × 4 = ______
Answer key
- 42
- 126
- 210
- 189
- 21
- 147
- 126
- 231
- 189
- 63
- 168
- 84
Word problems
Times tables are most useful when you can spot them in a question. Try these, then open each one to check:
- A box holds 21 pencils. How many pencils are in 4 boxes?
Answer
4 × 21 = 84 pencils. - Tickets cost $21 each. How much do 9 tickets cost?
Answer
9 × $21 = $189. - 105 chairs are set out in rows of 21. How many rows are there?
Answer
105 ÷ 21 = 5 rows. - A plant grows 21 millimetres a week. How much does it grow in 9 weeks?
Answer
9 × 21 = 189 millimetres.
Questions
What is 21 × 12?
252.
What is half of 21 × 8?
21 × 8 = 168, and half of that is 84, which is 21 × 4. Halving one factor halves the answer.
What is 21 times 0?
0. Any number multiplied by zero is zero, because zero groups of 21 contain nothing.
What is 21 × 7 and 21 × 8?
21 × 7 = 147 and 21 × 8 = 168. These two are the facts most people find hardest, so they are worth practising on their own.
Is 315 in the 21 times table?
Yes: 315 ÷ 21 = 15 with no remainder. 316 is not, because dividing it by 21 leaves a remainder of 1.
How do I learn the 21 times table quickly?
Learn it in order first, then use the patterns above and practise mixed questions; a few minutes a day works better than one long session.