01 / Double plus one
2k + k
3 × 7 is double 7, which is 14, plus 7 more. That makes 21.
Free tool
The 3 times table runs 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36. Read the table, see the digit sum pattern, hide the answers to test yourself, take a scored quiz, or print a chart or practice sheet. No sign-up and no limit.
Your settings and best scores stay in this browser only.
Worked out in your browser. Nothing is sent anywhere.
How it works
01 / Double plus one
3 × 7 is double 7, which is 14, plus 7 more. That makes 21.
02 / Digit sums
Add the digits of each answer and you get 3, 6 or 9, in that repeating order.
03 / Last digits
The ones digit goes 3, 6, 9, 2, 5, 8, 1, 4, 7, 0 and repeats every ten steps.
Guide
The 3 times table is the list of multiples of 3: 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36 up to 3 × 12. Its best trick is in the digits, because adding the digits of any answer gives 3, 6 or 9. The tool above shows the table, hides answers for a self-test, runs a scored quiz that explains every wrong answer, and prints a chart or sheet.
| Sum | Answer | A way to work it out |
|---|---|---|
| 3 × 1 | 3 | Double 1 is 2, plus 1 more = 3 |
| 3 × 2 | 6 | Double 2 is 4, plus 2 more = 6 |
| 3 × 3 | 9 | Double 3 is 6, plus 3 more = 9 |
| 3 × 4 | 12 | Double 4 is 8, plus 4 more = 12 |
| 3 × 5 | 15 | Double 5 is 10, plus 5 more = 15 |
| 3 × 6 | 18 | Double 6 is 12, plus 6 more = 18 |
| 3 × 7 | 21 | Double 7 is 14, plus 7 more = 21 |
| 3 × 8 | 24 | Double 8 is 16, plus 8 more = 24 |
| 3 × 9 | 27 | Double 9 is 18, plus 9 more = 27 |
| 3 × 10 | 30 | Double 10 is 20, plus 10 more = 30 |
| 3 × 11 | 33 | Double 11 is 22, plus 11 more = 33 |
| 3 × 12 | 36 | Double 12 is 24, plus 12 more = 36 |
Add the digits of each answer. 12 gives 1 + 2 = 3, 15 gives 6, 18 gives 9, 21 gives 3, 24 gives 6, 27 gives 9, 30 gives 3, 33 gives 6, 36 gives 9. The sums repeat 3, 6, 9. This gives you a test for divisibility by 3: a number is in the 3 times table if its digits add up to a number in the table. 249 gives 2 + 4 + 9 = 15, which is in the table, so 249 = 3 × 83.
Three is 2 + 1. For 3 × 8, double 8 to get 16, then add 8 for 24. For 3 × 12, double 12 to get 24 and add 12 for 36. If you know the 2 times table, you can find any fact in the 3 table with one more addition.
Because 3 is odd, the answers alternate: 3 is odd, 6 is even, 9 is odd, 12 is even. The ones digit goes 3, 6, 9, 2, 5, 8, 1, 4, 7, 0 and uses every digit once before it repeats. That is one reason the table can feel slippery: the ones digit never settles into a short cycle like it does in the 2, 4, 5 and 6 tables.
The 6 table is the 3 table doubled: 3 × 7 = 21 and 6 × 7 = 42. The 9 table is the 3 table tripled: 3 × 4 = 12 and 9 × 4 = 36. So the 3 table is worth learning well first.
Set Go up to to 20 and the tool shows these as well. For any of them, split the number: 3 × 13 is 3 × 10 plus 3 × 3, which is 30 + 9 = 39.
| Sum | Answer |
|---|---|
| 3 × 13 | 39 |
| 3 × 14 | 42 |
| 3 × 15 | 45 |
| 3 × 16 | 48 |
| 3 × 17 | 51 |
| 3 × 18 | 54 |
| 3 × 19 | 57 |
| 3 × 20 | 60 |
Learn 3, 6, 9, 12, 15 first, then 18 to 30. The last two, 33 and 36, are 3 × 11 (repeat the 3) and 3 × 12 (a dozen threes). Use the digit sum card above to check each answer as you go.
Next, try the 4 times table, or go back to the 2 times table. To see every table in one grid, use the times tables chart. To make your own cards, try the flashcard maker.
Questions
3 × 3 = 9.
3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36.
Add the digits of any answer, and keep adding until one digit is left. You always get 3, 6 or 9.
Add up its digits. If the total is in the 3 times table, so is the number.
3 × 7 = 21 and 3 × 8 = 24. Think of 21 as 7 + 14 and 24 as 8 + 16.
Only if you tick Ask both ways round. Then 3 × 7 and 7 × 3 are both in the mix.