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A level annuity-immediate pays Rs. 1 at the end of each year for years — payments at times . Its present value at is written (read “a angle n”).
CM1 Foundation · Theory of Interest Rates
Derive the annuity-immediate formula from a geometric series.
Recommended before this lesson — you can still read and practice below:
A level annuity-immediate pays Rs. 1 at the end of each year for years — payments at times . Its present value at is written (read “a angle n”).
This lesson derives from a geometric series and connects it to the equation of value.
Each payment of Rs. 1 at time has present value where . Summing:
This is a geometric series with first term and ratio .
At and : , ,
So Rs. 100 per year for 3 years has PV Rs. 272.30 at .
Problem. An loan requires payments of Rs. 8,000 at the end of each year for 5 years. With effective, find the present value at .
Solution.
Problem. Rs. 1 deposited at the end of each year for years at rate . The accumulated value at is .
For Rs. 500/year for 4 years at 5%: , so accumulation Rs. 2,155.
You should be able to (1) write , (2) value level annuity-immediates at , and (3) recognise the geometric-series origin. Practice and mastery checks below test that.
An annuity-immediate of Rs. 1 for years has present value equal to:
Find at effective to three decimal places.
Rs. 4,000 per year for 4 years (annuity-immediate), . PV at to the nearest rupee.
sums powers of:
Number of terms in PV of annuity-immediate for years is:
Find at to three decimals.
Find at to three decimals.
Rs. 2,500 per year for 3 years (immediate), . PV (nearest rupee).
Rs. 3,000 per year for 5 years at . PV (nearest rupee).
Derive and compute at to three decimals.
Rs. 5,000 per year for 4 years at (immediate). PV at (nearest rupee).
Pass each skill by answering correctly on 2 of 3 checks (fewer if fewer are available). Practice questions above are rehearsal — only mastery checks count toward progress. Retry wrong answers until you succeed.
0/2 verified
The closed form comes from summing:
Closed form requires:
First payment of annuity-immediate is discounted by factor:
Locked — complete prior skills first
Rs. 6,000 per year for 5 years at (annuity-immediate). PV at to the nearest rupee.
at to three decimals.
increases with when:
Locked — complete prior skills first
An annuity-immediate pays at:
Rs. 8,000 per year for 4 years, . PV (nearest rupee).
PV of Rs. annuity-immediate for years is:
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