# CCGPS CA 3.6.1 Example 1

- Author:
- Walch Education

The starting balance of Anna’s account is $1,250. She takes $30 out of her account each month.
How much money is in her account after 1, 2, and 3 months?
Find an equation to represent the balance in her account at any month.

- Use the description of the account balance to find the balance after each month.
- Determine the independent and dependent quantities.
- Determine if there is a common difference or common ratio that describes the change in the dependent quantity.
- Use the common difference to write an explicit equation.
- Evaluate the equation to verify that it is correct.

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