Problem Analysis

The problem requires us to calculate the total value of four separate investments in the year 2010. The rule is that each investment doubles in value every 5 years. We need to find the final value of each investment and then sum them up.

Calculating the Value of Each Investment in 2010

1. Investment made in 1990 (Rs. 5,000)
   • Time period: 1990 to 2010 = 20 years.
   • Number of 5-year doubling periods: 20 / 5 = 4.
   • Final Value = 5,000 × 2⁴ = 5,000 × 16 = 80,000.
2. Investment made in 1995 (Rs. 5,000)
   • Time period: 1995 to 2010 = 15 years.
   • Number of 5-year doubling periods: 15 / 5 = 3.
   • Final Value = 5,000 × 2³ = 5,000 × 8 = 40,000.
3. Investment made in 2000 (Rs. 5,000)
   • Time period: 2000 to 2010 = 10 years.
   • Number of 5-year doubling periods: 10 / 5 = 2.
   • Final Value = 5,000 × 2² = 5,000 × 4 = 20,000.
4. Investment made in 2005 (Rs. 5,000)
   • Time period: 2005 to 2010 = 5 years.
   • Number of 5-year doubling periods: 5 / 5 = 1.
   • Final Value = 5,000 × 2¹ = 5,000 × 2 = 10,000.

Total Amount Calculation

To find the total amount received, we sum the final values of all four investments:

Total Amount = 80,000 + 40,000 + 20,000 + 10,000

Total Amount = Rs. 1,50,000