Final answer:
Comparing two loan options: one with annual compound interest and another with continuous compounding, using their respective formulas to show variables and reason for choice. Analysis suggests the continuously compounded loan might be higher despite a lower rate. Calculations would provide exact repayment amounts for each option.
Step-by-step explanation:
The student's question involves comparing two different loan options with differing interest rate structures and determining which would be the more economical choice over a 4-year period.
Manipulation of Numerical Data
For option A (parents' loan), the compound interest formula is P(1 + r/n)^(nt), where P is the principal amount ($15,000), r is the annual interest rate (0.0355), n is the number of times interest is compounded per year (1), and t is the time in years (4).
For option B (bank loan), the continuously compounded interest formula is Pe^(rt), where P is the principal amount ($15,000), r is the annual interest rate (0.035), and t is the time in years (4).
Analysis of Numerical Data
Prior to calculations, one might conjecture that the loan with continuous compounding could be higher due to the nature of continuous growth, even though the interest rate is slightly lower.
Calculation results
The exact calculations, based on the formulas provided, would yield the total amounts of money Alf would need to repay for each loan after 4 years.