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A sum of 5000amountsto6050 in 2 years at compound interest. What is the rate of interest per annum?
8%
9%
10%
12%
10%
Compound interest represents the accumulation of interest on both the principal and the previously accumulated interest. In this case, the amount A grows from P to A over n years, following the geometric progression defined by the compound interest formula.
Compound interest represents the accumulation of interest on both the principal and the previously accumulated interest. In this case, the amount A grows from P to A over n years, following the geometric progression defined by the compound interest formula.
Think of it like a snowball rolling down a hill: it picks up more snow as it gets larger, just as interest earns more interest the longer it sits in the account.
A=P(1+100RтАЛ)n тАФ Compound Amount formula
CI=AтИТP тАФ Compound Interest formula
The principle operates on the mechanism of exponential growth where the principal increases by a factor of (1+100RтАЛ) each year. By rearranging A=P(1+100RтАЛ)n, we isolate the rate R using the square root method since n=2. This demonstrates the concept of time-value of money where interest compounds over time.
The rate of interest is applied to the accumulated balance, not just the initial principal.
For n=2, the ratio PAтАЛ is the square of the growth factor (1+100RтАЛ).
Compounding frequency significantly affects the final maturity amount.
Maximizes returns over long periods.
Accounts for the time-value of money.
Increases the burden of debt for borrowers.
Less intuitive than simple interest calculation.
Banking and financial savings accounts.
Investment growth projections in economics.
Given P=5000, A=6050, n=2. Then 6050=5000(1+100RтАЛ)2. Simplifying, 50006050тАЛ=1.21. Taking the square root of 1.21 gives 1.1, implying 100RтАЛ=0.1, so R=10%.
Option A (8%) results in 5000├Ч(1.08)2=5832. Option B (9%) results in 5000├Ч(1.09)2=5934.5. Option D (12%) results in 5000├Ч(1.12)2=6272.
C is correct тАФ The calculation reveals that a 10% annual interest rate applied over 2 years results in the exact maturity value of 6050.
When n=2, always look for a perfect square in the ratio PAтАЛ to quickly identify the growth factor (1+100RтАЛ).