In these lessons, we will look at some examples of adding and subtracting numbers in
scientific notation

(Scientific notation is called standard form in the UK.)

**Related Pages**

Converting Scientific Notation

Multiplying Scientific Notation

Dividing Scientific Notation

To add or subtract two numbers in scientific notation:

Step 1: Adjust the powers of 10 in the 2 numbers so that they have the same index. (Tip: It is easier to adjust the smaller index to equal the larger index).

Step 2: Add or subtract the numbers.

Step 3: Give the answer in scientific notation.

**Example:**

Evaluate 2 × 10^{3} + 3.6 × 10^{4}, giving your answer in
scientific notation.

**Solution:**

**Example:**

Evaluate 7 × 10^{5} – 5.2 × 10^{4}, giving your answer in
scientific notation.

**Solution:**

This video explains how to add and subtract numbers written in scientific notation, whether or not they have the same exponent.

**Examples:**

(3.769 × 10^{5}) + (4.21 × 10^{5})

(8.14 × 10^{-2}) - (2.01 × 10^{-2})

(7.58 × 10^{5}) + (2.871 × 10^{6})

(2.9785 × 10^{-8}) - (5.72 × 10^{-10})

(4.86 × 10^{3}) - (4.72 × 10^{3})

This video explains why when adding and subtracting numbers in scientific notation, you have to make sure the exponents are the same.

**Example:**

(7.1 × 10^{3}) + (5 × 10^{2})

This video reviews scientific notation and shows how to add and subtract in Scientific Notation.

Rule for scientific notation:

- If the exponent goes down, the decimal point goes right.
- If the decimal point goes right, the exponent goes down.
- If the exponent goes up, the decimal goes left.
- If the decimal point goes left, the exponent goes up.

This video explains how to do add and subtract in scientific notation without the use of a calculator.

- The powers of 10 must be the same in both terms in order to add/subtract.
- Once the power of 10 matches, just add or subtract.
- Adjust the answer to scientific notation.

Learn how to add and subtract in scientific notation.

Add and subtract numbers in different bases by rewriting their exponents to be the same.

**Example:**

(3.5 × 10^{4}) + (3.1 × 10^{5})

Try the free Mathway calculator and
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