Multiplying Decimals

Question:
Find the product of 0.5 × 3

Method 1: Simple Multiplication

Step 1: Ignore the Decimal First

  5
× 3
----
 15

Step 2: Put the Decimal Point

0.5 has 1 decimal place.
So, 15 becomes 1.5

Final Answer:

0.5 × 3 = 1.5

Method 2: Easy Understanding Method

0.5 means half.
Half of 3 = 1.5

So, 0.5 × 3 = 1.5

Multiplying Decimals

Question:
Find the product of 3.75 × 6

Step 1: Ignore the Decimal and Multiply

   375
×    6
-------
  2250

Step 2: Put the Decimal Point

3.75 has 2 decimal places.
So, 2250 becomes 22.50

Final Answer:

3.75 × 6 = 22.5

Easy Understanding Method:

3 × 6 = 18
0.75 × 6 = 4.5
18 + 4.5 = 22.5

Multiplying Decimals

Question:
Find the product of 50.2 × 4

Step 1: Ignore the Decimal and Multiply

   502
×    4
-------
  2008

Step 2: Put the Decimal Point

50.2 has 1 decimal place.
So, 2008 becomes 200.8

Final Answer:

50.2 × 4 = 200.8

Easy Understanding Method:

50.2 = 50 + 0.2

50 × 4 = 200
0.2 × 4 = 0.8

200 + 0.8 = 200.8

Multiplying Decimals

Question:
Find the product of 0.03 × 9

Step 1: Ignore the Decimal and Multiply

   3
×  9
-----
  27

Step 2: Put the Decimal Point

0.03 has 2 decimal places.
So, 27 becomes 0.27

Final Answer:

0.03 × 9 = 0.27

Easy Understanding Method:

0.03 means 3 hundredths.
3 hundredths × 9 = 27 hundredths.
27 hundredths = 0.27

Multiplying Decimals

Question:
Find the product of 453.03 × 7

Step 1: Ignore the Decimal and Multiply

   45303
×      7
-----------
  317121

Step 2: Put the Decimal Point

453.03 has 2 decimal places.
So, 317121 becomes 3171.21

Final Answer:

453.03 × 7 = 3171.21

Easy Understanding Method:

453.03 = 453 + 0.03

453 × 7 = 3171
0.03 × 7 = 0.21

3171 + 0.21 = 3171.21

Multiplying Decimals

Question:
Find the product of 4 × 0.7

Step 1: Ignore the Decimal and Multiply

  7
× 4
----
 28

Step 2: Put the Decimal Point

0.7 has 1 decimal place.
So, 28 becomes 2.8

Final Answer:

4 × 0.7 = 2.8

Easy Understanding Method:

0.7 means 7 tenths.
7 tenths × 4 = 28 tenths.
28 tenths = 2.8

Area of a Parallelogram

Question:
Find the area of the parallelogram whose base is 6.8 cm and height is 3.5 cm.

Step 1: Write the Formula

Area of Parallelogram = Base × Height
= 6.8 × 3.5

Step 2: Ignore the Decimal and Multiply

   68
×  35
------
  340
+2040
------
 2380

Step 3: Put the Decimal Point

6.8 has 1 decimal place
3.5 has 1 decimal place
Total decimal places = 2

So, 2380 becomes 23.80

Final Answer:

Area = 23.8 cm²

Diagram:

        Base = 6.8 cm
   ______________________
  /                     /
 /                     /  Height = 3.5 cm
/_____________________/

Area of a Rectangle

Question:
Find the area of the rectangle whose length is 23.7 cm and breadth is 15.2 cm.

Step 1: Write the Formula

Area of Rectangle = Length × Breadth
= 23.7 × 15.2

Step 2: Ignore the Decimal and Multiply

    237
×   152
---------
    474
   1185
+ 23700
---------
  36024

Step 3: Put the Decimal Point

23.7 has 1 decimal place
15.2 has 1 decimal place
Total decimal places = 2

So, 36024 becomes 360.24

Final Answer:

Area = 360.24 cm²

Diagram:

        Length = 23.7 cm
   -------------------------
   |                       |
   |                       |  Breadth = 15.2 cm
   |                       |
   -------------------------

Multiplying Decimal by 10

Question:
Multiply 2.57 × 10

Simple Trick

When we multiply a decimal number by 10, the decimal point moves one place to the right.

Step 1: Write the Number

2.57

Step 2: Move the Decimal One Place to the Right

2.57 → 25.7

Final Answer:

2.57 × 10 = 25.7

Easy Rule:

• ×10 → Move 1 place right
• ×100 → Move 2 places right
• ×1000 → Move 3 places right