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

Question

At this rate, how many weeks did it take Kendra to save $330?
A. 210
B. 4
C. 8
D. 5.2

Answer 1

To solve for the number of weeks it took Kendra to save $330 in her account, we can start with her initial balance and the amount she deposits each week.

1. Kendra's initial account balance is -$70.
2. She puts $50 into her account each week.
3. We want to find the number of weeks \( w \) it takes for her balance to reach $330.

The equation for Kendra's account balance after \( w \) weeks can be represented as:

\[ \text{Final balance} = \text{Initial balance} + (\text{Weekly deposit} \times \text{Number of weeks}) \]

Substituting the values:

\[ 330 = -70 + (50 \times w) \]

Now, we can add 70 to both sides of the equation:

\[ 330 + 70 = 50w \]

Which simplifies to:

\[ 400 = 50w \]

Next, we divide both sides by 50 to find the number of weeks \( w \):

\[ w = \frac{400}{50} = 8 \]

Thus, it took Kendra 8 weeks to save $330. The answer is:

C. 8