There's no need to feel pressured about double-digit multiplication. As long as you understand basic single-digit multiplication, you should be ready to do two-digit multiplication. Start by multiplying the ones digit in the bottom number by the ones digit in the number above. Then, multiply the units digit of the bottom number by the tens digit of the next top number. You also need to multiply the lower tens digit by the ones and tens digits of the upper number. After that, add up the two results to get the multiplication answer.
Step
Method 1 of 2: Calculating Two-Digit Multiplication by Two Digits
Step 1. Write the two two-digit numbers in succession (above each other)
Place one two-digit number in the top row and another two-digit number below it. While there's no right or wrong way to place a number, place a two-digit number ending in a 0 at the bottom (e.g. 40). This way, you can skip multiplication for that number.
For example, if you want to multiply 22 by 43, you can put 22 on the top row or vice versa (the same goes for 43)
Step 2. Multiply the units digit of the bottom row number by the unit digit of the number above it
For now, you don't need to think about the tens digit of the bottom row number. Just use the units digit of the bottom row of numbers and multiply by the units digits of the numbers above it. Write the result of the product just below the line.
For 22 x 43, multiply 3 by 2 to get 6
Step 3. Multiply the units digit of the lower number by the tens digit of the upper number
Use the same bottom number (ones digit) and multiply that number by the tens digit of the top number. After that, write the multiplication result under the row, just below the tens digit (aligned).
For example, for a 22 x 43 product, multiply 3 by 2 to get 6. Once the result is written down, the number at the bottom of the row is 66
Step 4. Place a zero under the first product
Before starting the next multiplication, place a zero under the unit digit of the first product. This zero serves as a space or blank space so you can multiply the digits of the lower tens of numbers.
If you get the number 66 as the result of the first multiplication, place the number 0 under the number 6 (units)
Step 5. Multiply the tens digit of the lower number by the units digit of the upper number
After doing the multiplication for the lower unit digits, multiply the lower tens digit by the upper units digit. Write the multiplication result next to the zeros you previously inserted.
For example, 4 x 2 = 8. Therefore, write the number 8 next to the number 0
Step 6. Multiply the lower tens digit by the upper tens digit
Write the multiplication result next to the number you just wrote down.
For 4 x 2, rewrite the number 8 next to the number 80 that was previously written
Step 7. Add the two products together to get the final answer
If there are no other digits in the number, you are ready to add the product of the two rows. The sum of the numbers in the two result lines is the final answer for the two-digit multiplication.
For example, add 66 + 880 so you get 946 as the final product
Method 2 of 2: Saving Results
Step 1. Multiply and save the calculation result that is greater than 9
If you multiply the units digit by the number above it and the result is greater than 9, you need to "store" the additional number above the top row number. Remember to write additional numbers above the tens digit of the top row number.
For example, if you multiply 96 x 8, you'll get 48 when you multiply 6 by 8. Don't write 48 at the bottom of the line. Instead, write the number 8 (the unit digit of the product) and "store" the number 4 (the tens digit of the product)
Step 2. Multiply the number by the tens digit of the top number and add the additional numbers previously stored
Multiply the unit digits of the lower number with the tens digit of the upper number as usual. After that, add the number stored in the multiplication result (the number recorded above the top tens digit).
For example, to multiply 96 x 8, multiply 8 by 9 to get 72. After that, add the 4 you saved earlier so you get 76. This way, the final product of this two-digit product is 768
Step 3. Continue multiplying and saving if necessary
If any of the numbers has more than two digits, continue multiplying and storing for each digit until you have completed all of them.
