christine deposits $50,000 into an account that pays simple interest at a rate of 4% per year. kevin…

christine deposits $50,000 into an account that pays simple interest at a rate of 4% per year. kevin deposits $50,000 into an account that also pays 4% interest per year. but it is compounded annually. find the interest christine and kevin earn during each of the first three years. then decide who earns more interest for each year. assume there are no withdrawals and no additional deposits. year interest christine earns (simple interest) interest kevin earns (interest compounded annually) who earns more interest? first $ $ christine earns more. kevin earns more. they earn the same amount. second $ $ christine earns more. kevin earns more. they earn the same amount. third $ $ christine earns more. kevin earns more. they earn the same amount.
Answer
Explanation:
Step1: Calculate simple - interest formula
The simple - interest formula is $I = Prt$, where $P$ is the principal amount, $r$ is the annual interest rate (in decimal form), and $t$ is the time in years. Given $P=$50000$, $r = 0.04$. For Christine (simple interest): For year 1 ($t = 1$): $I_{1s}=Prt=50000\times0.04\times1=$2000$ For year 2 ($t = 2$): $I_{2s}=Prt=50000\times0.04\times2=$4000$ For year 3 ($t = 3$): $I_{3s}=Prt=50000\times0.04\times3=$6000$
Step2: Calculate compound - interest formula
The compound - interest formula is $A=P(1 + r)^t$, where $A$ is the amount of money accumulated after $n$ years, including interest, $P$ is the principal amount, $r$ is the annual interest rate (in decimal form), and $t$ is the number of years the money is invested for. The interest earned $I=A - P$. For Kevin (compound interest): For year 1 ($t = 1$): $A_1=P(1 + r)^1=50000\times(1 + 0.04)^1=50000\times1.04=$52000$ $I_{1c}=A_1 - P=52000-50000=$2000$ For year 2 ($t = 2$): $A_2=P(1 + r)^2=50000\times(1 + 0.04)^2=50000\times1.04^2=50000\times1.0816=$54080$ $I_{2c}=A_2 - P=54080 - 50000=$4080$ For year 3 ($t = 3$): $A_3=P(1 + r)^3=50000\times(1 + 0.04)^3=50000\times1.124864=$56243.2$ $I_{3c}=A_3 - P=56243.2-50000=$6243.2$
Answer:
| Year | Interest Christine earns (Simple interest) | Interest Kevin earns (Interest compounded annually) | Who earns more interest? |
|---|---|---|---|
| First | $$2000$ | $$2000$ | They earn the same amount. |
| Second | $$2000$ | $$2080$ | Kevin earns more. |
| Third | $$2000$ | $$2163.2$ | Kevin earns more. |