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IAI Actuarial Core Principles · Actuarial Mathematics for Modelling · Interest rates over different time periods

The force of interest is a constant 5% per annum for the first 4 years and 7% per annum thereafter. What is the accumulated value at time 10 of Rs 1,00,000 invested at time 0, to the nearest rupee?

Sum the force of interest over time: 0.05 times 4 plus 0.07 times 6 equals 0.62. Accumulating gives 100,000 times e^0.62, about Rs 1,85,893. This value is not among the options, so the question is flawed.

  1. ARs 1,64,872
  2. BRs 1,82,212
  3. CRs 1,97,730
  4. DRs 2,01,375Correct
  5. Rs 2,22,554

Explanation

The integral is 0.05×4 + 0.07×6 = 0.20 + 0.42 = 0.62. The accumulated value is 1,00,000 × e^0.62 = 1,00,000 × 1.858928 = 1,85,893. This does not match any option, so the key is inconsistent.

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