Correct Answer - Option 1 : Rs.5000

**Formula:**

Let P = Principle, R = Rate of interest and N = time period

Simple interest = PNR/100

**Calculation:**

Let amount invested initially by P be Rs.a

Total amount he kept into savings at the end of second year = Rs.1352

Total amount he earned at the end of second year = 1352 × 100/20 = Rs.6760

Amount earned at the end of first year = a + a × 30 × 1/100 = Rs.13a/10

Amount invested for second year = 13a/10 × 80/100 = Rs.52a/50

Amount earned at the end of second year = 52a/50 + 52a/50 × 30 × 1/100 = Rs.(52a/50 × 13/10)

⇒ 52a/50 × 13/10 = 6760

⇒ a = 5000

**∴ The amount invested by P initially is Rs.5000.**

Amount kept in savings in a year = (Simple interest + sum invested) × 20/100

Amount invested in second year = (Simple interest + sum invested) × (100 - 20)/100