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E:\Working\Focus_Learning\Math_Genius_3_(11-09-2024)\Open_Files\CHAP_04
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Step 2: Multiply 42 by 1 ten. H t O
42 × 1 ten = 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 obtained in step 1 and H t O
step 2. 4 2
84 + 420 = 504 × 1 2
8 4 1st product
Thus, 42 × 12 = 504. + 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 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 1st Write 1680 in 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
by using the following steps:
Step 1: Multiply 232 by 3 ones. th H t O
232 × 3 ones = 696 2 3 2
Write 696 as first line product. × 2 3
6 9 6
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 second line product. 6 9 6
4 6 4 0
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