Question

Kendra’s savings account has a balance of −$70 . She puts $50 each week into her account. After a certain period of time, she has $330 in her account.

At this rate, how many weeks did it take Kendra to save $330?

Answer 1

To solve the problem, we start with Kendra's initial balance and the amount she adds each week, and then determine how long it takes to reach her target balance.

1. **Initial Balance**: Kendra's savings account starts at -$70.
2. **Weekly Contribution**: Kendra adds $50 each week.
3. **Target Balance**: Kendra wants to reach a balance of $330.

We can set up the following equation to represent her balance after \( w \) weeks:

\[
\text{Balance after } w \text{ weeks} = \text{Initial Balance} + (\text{Weekly Contribution} \times w)
\]

Substituting in her values:

\[
\text{Balance after } w \text{ weeks} = -70 + 50w
\]

We want this to equal $330:

\[
-70 + 50w = 330
\]

Now, we solve for \( w \):

1. Add 70 to both sides:

\[
50w = 330 + 70
\]

\[
50w = 400
\]

2. Divide both sides by 50:

\[
w = \frac{400}{50}
\]

\[
w = 8
\]

So, it took Kendra **8 weeks** to save $330 in her account.