Explain Adding and Subtracting in Scientific Notation?

To add or subtract numbers in scientific notation, the numbers must be expressed so that they have the same exponent.

To make the exponents the same, the decimal must be moved.

Each time the decimal is moved one place to the left, the exponent increases by one. Each time the decimal is moved to the right, the exponent decreases by one.

Example 1: Evaluate 5.6 X 10³ + 8.1 X.10⁴.

5.6 X 10³ + 8.1 X.10⁴ = 5600 + 81000 = 86600 = 8.66 X 10⁴.

Example 2: Evaluate 1.3 X 10² + 4.8 X 10³.

1.3 X 10² + 4.8 X 10³ = 130 + 4800 = 4930 = 4.93 X 10³.