Page 80 - Touchpad Mathematics_Ver1.0_C4

Step 3. Multiply the hundreds and add the carried over hundreds. H T O
2 × 4 = 8 hundreds
8 hundreds + 1 hundred = 9 hundreds 1 2

So, 245 × 4 = 980. 2 4 5
× 4

9 8 0
Exercise 4C

1. Find the product.
a. 3 0 b. 2 2 c. 1 2 3 d. 2 4 3

× 2 × 4 × 3 × 2

2. Find the product.
a. 2 6 b. 8 8 c. 9 6 7 d. 6 9 4

× 3 × 9 × 3 × 4

3. Write the numbers in columns and find the product in your notebook.
a. 23 × 3 = _____ b. 16 × 6 = _____ c. 77 × 6 = _____
d. 83 × 8 = _____ e. 326 × 3 = _____ f. 436 × 7 = _____

g. 784 × 4 = _____ h. 546 × 7 = _____ i. 642 × 5 = _____

Multiplication by a 2-digit nuMber

Multiplication of a 2- and 3-digit number by a 2-digit number (Without regrouping)

example 1. Multiply 42 by 12.
Solution. Here, the multiplier 12 = 1 ten + 2 ones = 10 + 2. So, we multiply 42 by 12
stepwise as shown below.
Step 1. Multiply 42 by Step 2. Multiply 42 Step 3. Add the partial products.
the ones. by the tens.
H T O
H T O 4 2

H T O 4 2 × 1 2
× 1 2
4 2 8 4
× 1 2 8 4 + 4 2 0

8 4 4 2 0
5 0 4

42 × 2 = 84 42 × 10 = 420 84 + 420 = 504
So, 42 × 12 = 504.

78 Mathematics 3