Final answer:
To show how much money your friend and you will save over time, use the equations Amount Saved = Initial Amount + (Saving Rate × Number of Weeks), where the initial amounts are $220 and $260 respectively and the saving rate is $100 per week.
Step-by-step explanation:
To write an equation that shows how much money your friend will save over time, you can use the formula:
Amount Saved = Initial Amount + (Saving Rate × Number of Weeks)
For your friend, who starts with $220 and saves $100 a week, the equation would be:
Amount Saved = $220 + ($100 × Number of Weeks)
To write an equation that shows how much money you will save over time, you can use the same formula:
Amount Saved = $260 + ($100 × Number of Weeks)