## Adding with exponential notation

To add two numbers by using exponential notation, you begin by expressing each number as a coefficient and a power of 10. In this example, you add these numbers,by following these steps:

**Convert both numbers to the same power of 10.****Add the coefficients.****Join your new coefficient to the shared power of 10.**

## Subtracting with exponential notation

To subtract numbers in exponential notation, you follow the same steps but subtract the coefficients. Here’s an example:0.0743 – 0.0022

To perform the subtraction, follow these steps:**Convert both numbers to the same power of 10.****Subtract the coefficients.**7.43 – 0.22 = 7.21**Join your new coefficient to the shared power of 10.**

## Practice questions

**Add the following:****Use exponential notation to subtract the following:**9,352 – 431

## Answers and Explanations

**The correct answer is**Because the numbers are each already expressed with identical powers of 10 (in this case, 10^{–6}), you can simply add the coefficients: 398 + 147 = 545 Then join the new coefficient with the original power of 10.**The correct answer is**(or an equivalent expression). First, convert the numbers so each uses the same power of 10: Here, you’ve picked 10², but any power is fine as long as the two numbers have the same power. Then subtract the coefficients: 93.52 – 4.31 = 89.21 Finally, join the new coefficient with the shared power of 10.