Operations on Decimals-Gr 6-Solved Examples

Solved Examples and Worksheet for Operations on Decimals

Q1Find 50 + 0.3 + 0.003 in standard form.
A. 5.033
B. 50.33
C. 50.033
D. 50.303

Solutions

Step: 1

50 + 0.3 + 0.003

[Original Expression.]

Step: 2

= 50.303

[Add the terms in the expression.]

Step: 3

50.303 is the standard form.

Correct Answer is : 50.303

Q2Find the sum of 0.2 and 5.21.
A. 5.23
B. 5.410
C. 5.01
D. 0.721

Solutions

Step: 1

0.2 + 5.21

[Original values.]

Step: 2

0.20
+ 5.21
--------
5.410
--------

[Line up decimal points and put zeros to make columns even.]

[Add.]

Step: 3

The sum of 0.2 and 5.21 is 5.410

Correct Answer is : 5.410

Q3Find the sum of 6.296 and 5.

A. 11.296
B. 11.196
C. 11.096
D. 11.496

Solutions

Step: 1

6.296 + 5

[Original values.]

Step: 2

6.296
+ 5.000
---------
11.296
---------

[Line up decimal points and put zeros to make columns even.]

[Add.]

Step: 3

The sum of 6.296 and 5 is 11.296

Correct Answer is : 11.296

Q4Find the sum of 0.007 and 0.09.

A. 0.097
B. 0.016
C. 0.16
D. 0.10

Solutions

Step: 1

0.007 + 0.09

[Original values.]

Step: 2

	0.007
+	0.090	[Line up decimal points and put zero to make columns even.]

	0.097	[Add.]

Step: 3

The sum of 0.007 and 0.09 is 0.097

Correct Answer is : 0.097

Q5Find the difference between 4.6 and 1.4.
A. 6.0
B. 3.2
C. 4.6
D. 7.8

Solutions

Step: 1

4.6 - 1.4

[Original values.]

Step: 2

4.6
- 1.4
-----
3.2
-----

[Line up decimal points and make columns even.]

[Subtract.]

Step: 3

The difference between 4.6 and 1.4 is 3.2

Correct Answer is : 3.2

Q6Find the difference between 9.12 and 5.1.
A. 14.32
B. 4.12
C. 4.02
D. 14.22

Solutions

Step: 1

9.12 - 5.1

[Original values.]

Step: 2

9.12
- 5.10
-------
4.02
-------

[Line up decimal points and add trailing zeros to make columns even.]

[Subtract.]

Step: 3

The difference between 9.12 and 5.1 is 4.02

Correct Answer is : 4.02

Q7Find the difference between 3.96 and 2.73.

A. 6.69
B. 5.19
C. 3.96
D. 1.23

Solutions

Step: 1

	3.96
-	2.73

[Line up decimal points.]

Step: 2

	3.96
-	2.73

	1.23

[Subtract.]

Step: 3

The difference between 3.96 and 2.73 is 1.23.

Correct Answer is : 1.23

Q8Find the missing number in the equation 3.6 + 3.4 = ____ + 9.3.
A. -2.3
B. -7
C. 7
D. 2.3

Solutions

Step: 1

3.6 + 3.4 = ____ + 9.3

[Original equation.]

Step: 2

Let x be the missing number.

Step: 3

3.6 + 3.4 = x + 9.3

[Modified equation.]

Step: 4

7 = x + 9.3

[Add.]

Step: 5

7 - x = x + 9.3 - x

[Subtract x from both sides.]

Step: 6

7 - x = 9.3

[Simplify.]

Step: 7

- x = 9.3 - 7

[Subtract 7 from both sides.]

Step: 8

- x = 2.3

[Simplify.]

Step: 9

x = -2.3

[Multiply by -1 on both sides.]

Step: 10

The missing number is -2.3.

Correct Answer is : -2.3

Q9Find the product of 6.333 and 0.6.
A. 6.4232
B. 4.9232
C. 3.7998
D. 3.2768

Solutions

Step: 1

6.333 × 0.6

[Original expression.]

Step: 2

6.333

× 0.6

................

3.7998

[3 decimal places.]
[1 decimal place.]

[4 decimal places are required. Place the decimal point so that there are 4 decimal places in the product.]

Step: 3

The product of 6.333 and 0.6 is 3.7998

Correct Answer is : 3.7998

Q10Solve the equation x ÷ 0.5 = 0.37.

A. 0.185
B. 0.205
C. 0.175
D. 0.195

Solutions

Step: 1

x ÷ 0.5 = 0.37

[Original expression.]

Step: 2

x = 0.37 x 0.5

[Multiply each side with 0.5.]

Step: 3

	0.37
	x 0.5

	0.185

[2 decimal places.]
[1 decimal place.]

[3 decimal places are required. Insert zeros and place the decimal point so that there are 3 decimal places in the product.]

Step: 4

The value of x is 0.185.

Correct Answer is : 0.185

Q11Find the value of p in the expression p ÷ 3.9 = 0.003.

A. 0.1170
B. 1.1700
C. 0.0117
D. 0.0011

Solutions

Step: 1

p ÷ 3.9 = 0.003

[Original expression.]

Step: 2

p = 0.003 x 3.9

[Multiply each side with 3.9.]

Step: 3

    0.003
  x   3.9
_______
     0027
+ 0009
_______
   0.0117

[Three decimal places.]
[1 decimal plcae.]

[Multiply with 9.]
[Multiply with 3.]

[4 decimal places are required. Insert two zeros and place the decimal point so that there are 4 decimal places in the product.]

Step: 4

The value of p is 0.0117

Correct Answer is : 0.0117

Q12Find the product of 2.4 and 1.5.

A. 3.50
B. 3.60
C. 3.80
D. 3.70

Solutions

Step: 1

2.4 × 1.5

[Original expression.]

Step: 2