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Step 2: Multiply 42 by 1 ten. H t O

42 × 1 ten = 42 tens = 420 ones 4 2
× 1 2
Write 420 as the second line product. 8 4 1st product

4 2 0 2nd product

Step 3: Add the products from step 1 and step 2. H t O

84 + 420 = 504 4 2
× 1 2
Thus, 42 × 12 = 504. 8 4 1st product
+ 4 2 0 2nd product
5 0 4 Sum

Example 2: Multiply 56 by 32.

Solution: Expand the multiplier 32 as 3 tens + 2 ones. Now, follow these steps.
Step 1: Multiply 56 Step 2: Multiply 56 by 3 tens. Step 3: Add the products.
by 2 ones. 56 × 3 tens = 56 × 30 ones 112 + 1680 = 1792

56 × 2 ones = 112 = 1680
Write 112 in the 1st Write 1680 in the 2nd product
product line. line. th H t O

H t O th H t O 5 6
5 6 5 6 × 3 2
1 1 2
× 3 2 × 3 2 + 1 6 8 0 1st product
1 1 2 1st product 1 1 2 1st product 1 7 9 2 2nd product
Sum
1 6 8 0 2nd product

Thus, 56 × 32 = 1792.

Multiplication of a 3-digit number by a 2-digit number

Example 3: Multiply 232 by 23.

Solution: Expand the multiplier 23 as 20 + 3 = 2 tens + 3 ones and multiply 232 with it
using the following steps:
Step 1: Multiply 232 by 3 ones. th H t O
232 × 3 ones = 696 ones 2 3 2
Write 696 as the first line product. × 2 3

6 9 6 1st product
Step 2: Multiply 232 by 2 tens. th H t O

232 × 2 tens = 232 × 20 ones = 4640 ones 2 3 2
× 2 3
Write 4640 as the second line product. 6 9 6 1st product

4 6 4 0 2nd product

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