Multiplication of Two Same-Digits Number and One-Digit Number

1. 22 x 9 =

2. 33 x 8 =

3. 44 x 7 =

4. 55 x 6 =

1. 22 x 9 = ; 2 x 9 = 18. Write 1 & 8 with one-digit apart. They will be the first and third digits of the answer. Now, for the second digit, add the first and third digits, which in this example are 1 & 8. Their sum is 9. Therefore, the answer is 198.

2. 33 x 8 = ; 3 x 8 = 24. Write 2 & 4 with one-digit apart. They will be the first and third digits of the answer. Now, for the second digit, add the first and third digits, which in this example are 2 & 4. Their sum is 6. Therefore, the answer is 264.

3. 44 x 7 = ; 4 x 7 = 28. Write 2 & 8 with one-digit apart. They will be the first and third digits of the answer. Now, for the second digit, add the first and third digits, which in this example are 2 & 8. Their sum is 10. Write 0 as the second digit, and carry 1. Adding them, the answer is 308.

4. 55 x 6 = ; 5 x 6 = 30. Write 3 & 0 with one-digit apart. They will be the first and third digits of the answer. Now, for the second digit, add the first and third digits, which in this example are 3 & 0. Their sum is 3. Therefore, the answer is 330

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You may notice that I made the multiplication from left to right. It actually has a purpose.You can immediately tell what's the first digit or answer. This will be the beginning of solving it orally.

You'll be amazed that you can solve it orally if you just continue practicing.