Question

bobby borrowed $500 at 12 percent simple annual interest. he paid back $680 to pay off the loan. how many years did it take bobby to pay back the loan?

3
4
11
12

Explanation:

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<reasoning>

Calculate the total interest paid

Using the Total Payback Calculation knowledge point
\[

$$\begin{aligned} I &= A - P \\ I &= 680 - 500 \\ I &= 180 \end{aligned}$$

\]

Solve for the time in years

Using the Simple Interest Formula knowledge point
\[

$$\begin{aligned} I &= P \cdot r \cdot t \\ 180 &= 500 \cdot 0.12 \cdot t \\ 180 &= 60 \cdot t \\ t &= \frac{180}{60} \\ t &= 3 \end{aligned}$$

\]
</reasoning>

<answer>
<mcq-correct>(A) 3</mcq-correct>
<mcq-option>(B) 4</mcq-option>
<mcq-option>(C) 11</mcq-option>
<mcq-option>(D) 12</mcq-option>
</answer>

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Answer:

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<reasoning>

Calculate the total interest paid

Using the Total Payback Calculation knowledge point
\[

$$\begin{aligned} I &= A - P \\ I &= 680 - 500 \\ I &= 180 \end{aligned}$$

\]

Solve for the time in years

Using the Simple Interest Formula knowledge point
\[

$$\begin{aligned} I &= P \cdot r \cdot t \\ 180 &= 500 \cdot 0.12 \cdot t \\ 180 &= 60 \cdot t \\ t &= \frac{180}{60} \\ t &= 3 \end{aligned}$$

\]
</reasoning>

<answer>
<mcq-correct>(A) 3</mcq-correct>
<mcq-option>(B) 4</mcq-option>
<mcq-option>(C) 11</mcq-option>
<mcq-option>(D) 12</mcq-option>
</answer>

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