1. **Problem Statement:** Ramu borrowed 1000 at 10% per annum simple interest for 3 years, but after the first year, the interest rate was revised to 12% per annum. We need to find the total amount he will pay after 3 years.
2. **Formula for Simple Interest:**
Simple Interest (SI) = $P \times R \times T \div 100$
where $P$ = principal, $R$ = rate of interest per annum, $T$ = time in years.
3. **Step 1: Calculate interest for the first year at 10%**
$SI_1 = 1000 \times 10 \times 1 \div 100 = 100$
4. **Step 2: Calculate interest for the next 2 years at 12%**
$SI_2 = 1000 \times 12 \times 2 \div 100 = 240$
5. **Step 3: Calculate total interest for 3 years**
$SI_{total} = SI_1 + SI_2 = 100 + 240 = 340$
6. **Step 4: Calculate total amount to be paid**
Total Amount = Principal + Total Interest = $1000 + 340 = 1340$
**Final Answer:** Ramu will pay a total amount of 1340 after 3 years.
Simple Interest Revised
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