TablesHow to say the table of 23
23 one is 23, 23 twos are 46, 23 threes are 69, 23 fours are 92, 23 fives are 115, 23 sixes are 138, 23 sevens are 161, 23 eights are 184, 23 nines are 207, 23 tens are 230.
A quick way to work it out
Twenty times plus three times. For 23 × 4: 80 + 12 = 92. For 23 × 7: 140 + 21 = 161.
Patterns in the table of 23
- Last digit. The last digits of the first ten answers are 3, 6, 9, 2, 5, 8, 1, 4, 7 and 0. Each digit from 0 to 9 appears exactly once, which happens only for numbers ending in 1, 3, 7 or 9. After × 10 the same order repeats.
- Odd and even. 23 is odd, so the answers go odd, even, odd, even: 23, 46, 69, 92, 115 and 138. An odd number times an odd number is odd, and times an even number is even.
- Digit totals. Add the digits of each answer until one digit is left. For the first nine answers you get 5, 1, 6, 2, 7, 3, 8, 4 and 9: every digit from 1 to 9, once each. This happens for every number that is not a multiple of 3.
- Steps of 23. Each answer is 23 more than the one above it. So if 23 × 7 slips your mind, take 23 × 6 = 138 and add 23 to get 161.
- Total of the first ten. Add the first ten answers and you get 1265. That is 55 × 23, because 1 + 2 + 3 and so on up to 10 is 55.
How the table of 23 is built
23 is a prime number: no smaller table contains it, apart from the table of 1. So 23 × 1 = 23 is the first time 23 shows up anywhere on a multiplication chart, and its table cannot be made by doubling or tripling a smaller one. The square of 23 is 23 × 23 = 529. On a multiplication chart the squares lie on the diagonal line from top left to bottom right.
Split it. Above 10, the sure method is to split the number into tens and units. 23 × 8 is 20 × 8 plus 3 × 8, which is 160 + 24 = 184.
Where you meet 23
The number 23 is prime, so nothing smaller helps except splitting it into 20 and 3. One hour before midnight is 23:00 on a 24-hour clock.
Division facts from this table
Every line gives a division fact for free. From 23 × 7 = 161 you know that 161 ÷ 23 = 7 and 161 ÷ 7 = 23. To divide a number by 23, look for it in the answers above: 207 is on line 9, so 207 ÷ 23 = 9. More on this in division from tables.
Try these
Tap a question to see the answer.
23 × 6 = ?
138. One way: 23 × 5 = 115, and one more 23 makes 138.
? × 23 = 207
9, because 9 × 23 = 207.
161 ÷ 23 = ?
7. Division reads the table backwards: 23 × 7 = 161.
Each row in the hall has 23 chairs. How many chairs are in 9 rows?
23 × 9 = 207 chairs.
Which of these is not in the table of 23: 69, 115, 162 and 184?
162. The others are 23 × 3, 23 × 5 and 23 × 8.
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