Musa borrows N10.00 at 2% per month simple interest and repays N8.00 after 4 months. How much does he still owe?

1. Analyze the Question

We need to calculate the total amount Musa owes after 4 months, including the interest accrued on the principal, and then subtract the amount he has already repaid.

2. Explain the Concept

To solve this, we use the Simple Interest formula: Simple Interest (I) = (P × R × T) / 100 Where:

• P = Principal (the amount borrowed) = N10.00
• R = Rate per month = 2%
• T = Time in months = 4 months

The Total Amount (A) to be repaid is the Principal plus the Interest: A = P + I

Finally, the Balance Owed is: Balance = Total Amount (A) - Repayment

3. Show the Solution

Step 1: Calculate the Interest (I) $I = \frac{P \times R \times T}{100}$ $I = \frac{10 \times 2 \times 4}{100}$ $I = \frac{80}{100}$ $I = N0.80$

Step 2: Calculate the Total Amount (A) Musa owes after 4 months $A = P + I$ $A = 10.00 + 0.80$ $A = N10.80$

Step 3: Calculate the remaining balance after the repayment Musa repaid N8.00. $Balance = 10.80 - 8.00$ $Balance = N2.80$

4. Identify the Answer

Comparing our result to the options provided, we see that N2.80 corresponds to option C.

5. Exam Tip

When dealing with "Simple Interest" questions in JAMB, always pay close attention to the unit of time. If the rate is given "per month," ensure your time (T) is also in months. If the rate was "per annum" (per year) but the time was in months, you would have to convert the time to years (e.g., 4 months = 4/12 years).