Question

Rate of interest for the first 2 years is 3% per annum next 3 years is 8% per annum and for a period beyond 5 years is 10% per annum A man received an interest 1520 after 6 years. Find the amount to be invested?

• A. 3500
• B. 4100
• C. 3800
• D. 3650

Answer 1

Answer:

C. 3800

• Let the principal amount be 'P'.

• Period 1: First 2 years at 3% per annum.

  • Interest for the first 2 years (SI1) = (P × 3 × 2) / 100 = 6P / 100

• Period 2: Next 3 years (from year 3 to year 5) at 8% per annum.

  • Interest for the next 3 years (SI2) = (P × 8 × 3) / 100 = 24P / 100

• Period 3: For the period beyond 5 years. The total time is 6 years, so this period is for 6 - 5 = 1 year, at 10% per annum.

  • Interest for the 6th year (SI3) = (P × 10 × 1) / 100 = 10P / 100

• Total Interest: The sum of interests from all periods is given as 1520.

  • Total SI = SI1 + SI2 + SI3

  • 1520 = (6P / 100) + (24P / 100) + (10P / 100)

• Solving for Principal (P):

  • Combine the terms: 1520 = (6P + 24P + 10P) / 100

  • 1520 = 40P / 100

  • Simplify the fraction: 1520 = 2P / 5

  • Isolate P: P = (1520 * 5) / 2

  • Calculate P: P = 7600 / 2

  • P = 3800