Original practice · fully worked
Original variant: within-year accumulation factor inferred from an equivalent biennial annuity
A ten-year annuity pays equal fractions throughout each year. The accumulated value at each year-end of that year's fractional payments is A. An equivalent annuity pays 2.40 at years 2, 4, 6, 8, and 10. The two-year accumulated-annuity factor is 2.10. Calculate A.
- A
1.03 - B
1.09 - C
1.14 - D
1.20 - E
1.26
Answer and calculation
The annuity-value cancellation gives the biennial payment equal to A times the two-year accumulated-annuity factor. Therefore A = 2.40/2.10 = 1.1429, choice C.
Setup
Setup
Annualize each year's fractional block to amount A at the corresponding year-end.
PVX=Aa10∣i Model
Model
Equating with the five biennial payments yields the same simplification as grouping the ten years in pairs.
2.40=As2∣i Compute
Compute
Using the supplied two-year factor gives A = 1.142857.
A=2.102.40=1.14285714 Answer
Answer
The within-year accumulated amount is 1.1429, selecting choice C.
A≈1.1429(C)