Multiplication Facts: 9s, 10s, 11s, 12s
Multiplication facts for 9s, 10s, 11s, and 12s are mastered in Grade 4, Saxon Math Intermediate 4 Chapter 4. A key pattern for the 9s multiplication table is that the two digits of any product always add up to 9. For 9 times 7: subtract 1 from 7 to get the first digit (6), then ask what adds to 6 to make 9 (answer: 3), giving 63. Students verify: 6 plus 3 equals 9. This digit-sum trick aids quick mental recall and helps students self-check answers, building multiplication fluency needed for division and fractions.
Key Concepts
New Concept Also notice that the two digits of each product add up to nine.
What’s next Next, you’ll apply this pattern finding skill to master multiplication facts for 9s, 10s, 11s, and 12s through practice problems.
Common Questions
What is the digit-sum trick for 9s multiplication facts?
For any single-digit number times 9, the two digits of the product always add up to 9. For 9 times 8: subtract 1 from 8 to get 7, then 7 plus 2 equals 9, so the answer is 72.
How do I use the digit-sum pattern to find 9 times 7?
Subtract 1 from 7 to get the tens digit (6). Find the number that adds to 6 to make 9 (answer: 3). The product is 63.
What is a pattern for the 10s multiplication facts?
Multiplying by 10 always produces a number ending in zero. Just append a zero to the other factor: 10 times 7 equals 70.
Are the 11s multiplication facts easy to memorize?
Yes, for single digits: 11 times any digit 1–9 produces a two-digit number where both digits are the same (11 times 4 equals 44).
How do the 12s facts relate to the 10s and 2s facts?
Multiply by 10 and by 2, then add the results. For 12 times 7: 10 times 7 equals 70, plus 2 times 7 equals 14, total 84.