Question

Suppose you get $1000 from your uncle. you deposited that money in a bank and added $15 per month.

Write an equation to model how much money you have deposited after m months. Let s be the amount you have deposited.


What equation would you solve to figure out how many months it would take to save $10,000 dollars?


How many months would it take to save $10,000?

Answer 1

s = 1000 + 15m

Save $10,000 equation: 10,000 + 15 m

Months it takes to save = 600 months

Explanation:

You first deposit the $1000 your uncle gave you and then, each month, you add $15. So the first month the account will have,

1000 + 15

After the second month, it will have,

1000 + 15 + 15

And so on. Therefore, the equation that models your savings s after m months is,

s = 1000 + 15m

If we want to find how many months it will take to save $10,000 we have to solve the equation for s = 10,000:

10,000 = 1000 + 15m

To solve it, subtract 1000 from both sides of the equation,

10,000 - 1000 = 1000 - 1000 + 15m

9000 = 15m

And divide both sides by 15,

9000/55 = 55m/55

600 = m

It will take 600 months to save $10,000.