 # Add and Subtract Numbers in Standard Form (1)

In this worksheet, students add and subtract numbers written in standard form. Key stage:  KS 4

Curriculum topic:  Number

Difficulty level:   ### QUESTION 1 of 10

Standard (index) form is a shorthand way of writing a very large or a very small number.

It is written as a  number between 1 and 10 (but not equal to 10) multiplied by a power of 10, for example:

1.1223392 × 105 = 112233.92

6.94 x 10-4 = 0.000694

When we add and subtract numbers in standard form, we must first convert them to real numbers, then carry out the calculation before converting back to standard form.

Example 1

5.1 x 106  +   3 x 104

5.1 x 106  = 5100000

3 x 104 = 30000

Add to get 5130000

5130000 = 5.13 x 106

So answer is 5.13 x 106

Example 2

Subtract

5.2 x 105  -   9 x 104

5.2 x 105  = 520000

9 x 104 = 90000

Subtract to get 430000

430000 = 4.3 x 105

So answer is 4.3 x 105

4 x 106  +   6 x 104

(The answer must be in standard form)

1 x 1024

4.06 x 106

4.6 x 106

3 x 105  +   2 x 104

(The answer must be in standard form)

3.2 x 105

5 x 1020

6 x 105

Subtract

3 x 105  -   4 x 104

(The answer must be in standard form)

2.6 x 105

3.4 x 105

3.4 x 104

Subtract

5 x 109  -   4 x 106

(The answer must be in standard form)

1 x 103

20 x 103

4.996 x 109

1 x 103  +   4 x 106

(The answer must be in standard form)

4.1 x 106

5 x 103

4.001 x 106

Subtract

4 x 103  -   4 x 107

(The answer must be in standard form)

1 x 10-4

-3.9996 x 107

3.9996 x 104

Subtract

4.2 x 105  -   4 x 107

(The answer must be in standard form)

-3.958 x 107

2 x 1012

0.2 x 10-2

6.3 x 105  +   3.24 x 107

(The answer must be in standard form)

3.303 x 107

3.87 x 107

9.54 x 1012

3.313 x 105  +   4.28 x 104

(The answer must be in standard form)

7.593 x 109

12.2 x 109

3.741 x 105

Subtract

2.5 x 105  -   6.35x 107

(The answer must be in standard form)

3.85 x 107

-6.325 x 107

3.85 x 10-2

• Question 1

4 x 106  +   6 x 104

(The answer must be in standard form)

4.06 x 106
• Question 2

3 x 105  +   2 x 104

(The answer must be in standard form)

3.2 x 105
• Question 3

Subtract

3 x 105  -   4 x 104

(The answer must be in standard form)

2.6 x 105
• Question 4

Subtract

5 x 109  -   4 x 106

(The answer must be in standard form)

4.996 x 109
• Question 5

1 x 103  +   4 x 106

(The answer must be in standard form)

4.001 x 106
• Question 6

Subtract

4 x 103  -   4 x 107

(The answer must be in standard form)

-3.9996 x 107
• Question 7

Subtract

4.2 x 105  -   4 x 107

(The answer must be in standard form)

-3.958 x 107
• Question 8

6.3 x 105  +   3.24 x 107

(The answer must be in standard form)

3.303 x 107
• Question 9

3.313 x 105  +   4.28 x 104

(The answer must be in standard form)

3.741 x 105
• Question 10

Subtract

2.5 x 105  -   6.35x 107

(The answer must be in standard form)