PPSC Excise and Taxation Inspector 2018 Question Paper

Answer: B - Rs. 800

Step by step calculation:

Step 1 - Find Simple Interest for 2 years:

Amount in 5 years = Rs. 1040 ,Amount in 3 years = Rs. 944

SI for (5−3) = 2 years = 1040 − 944 = Rs. 96

Step 2 - Find SI for 1 year:

SI per year = 96 ÷ 2 = Rs. 48

Step 3 - Find SI for 3 years:

SI for 3 years = 48 × 3 = Rs. 144

Step 4 - Find Principal:

Principal = Amount in 3 years - SI for 3 years Principal = 944 - 144 = Rs. 800

The key insight:

• In Simple Interest, the interest earned every year is equal
• So, difference in amounts over any period = SI for that period
• Difference between 5yr and 3yr amounts = SI for exactly 2 years
• Everything else follows from that