This Exam FM sample reference tests Annuities. Discounting the time-25 balance and all deposits through the two interest-rate regimes requires 3% factors through year 10 and 2% factors thereafter. The only expression with the correct split and timing is choice D.
These notes identify the calculation error associated with each wrong letter when that error is reproducible.
AChoice A (= 10) does not satisfy the time-0 equation with deposits at times 0 through 25 and the rate change after time 10; no distinct standard one-step error is identifiable.
BChoice B (= 10 16) does not satisfy the time-0 equation with deposits at times 0 through 25 and the rate change after time 10; no distinct standard one-step error is identifiable.
CChoice C (= 10) does not satisfy the time-0 equation with deposits at times 0 through 25 and the rate change after time 10; no distinct standard one-step error is identifiable.
EChoice E (= 10) does not satisfy the time-0 equation with deposits at times 0 through 25 and the rate change after time 10; no distinct standard one-step error is identifiable.
Original practice · fully worked
Original variant: deposit required under a two-stage annual crediting schedule
A saver deposits the same amount at times 0, 1, 2, 3, 4, and 5. The account earns 4% in each of the first three years and 3% in each of the next two years. Immediately after the time-5 deposit the balance must be 50,000. Calculate each deposit.
A 6,885.92
B 7,268.47
C 7,651.02
D 8,033.57
E 8,416.13
Variant answer in brief
Accumulating each of the six deposits through the appropriate 4% and 3% periods gives a combined factor of 6.535074. Dividing 50,000 by that factor gives deposit 7,651.02, choice C.
Setup
Setup
Use time 5 as the comparison date and retain the exact rate regime traversed by each deposit.
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