3. savings account malik deposited $1,050 in a savings account, and it earned $241.50 in simple interest…

3. savings account malik deposited $1,050 in a savings account, and it earned $241.50 in simple interest after four years. find the interest rate on maliks savings account.\n5. retirement mr. pham has $410,000 in a retirement account that earns 3.85% simple interest each year. find the amount earned each year by this investment.\n7. lottery raj won $900,000 in a regional lottery. after paying $350,000 in taxes, he invested the remaining money in a savings account at 4.25% simple interest. how much money is in the account if raj makes no deposits or withdrawals for two years?
Answer
3.
Explanation:
Step1: Recall simple - interest formula
The simple - interest formula is $I = Prt$, where $I$ is the interest, $P$ is the principal amount, $r$ is the interest rate, and $t$ is the time in years. We need to solve for $r$. Rearranging the formula gives $r=\frac{I}{Pt}$.
Step2: Identify values of $I$, $P$, and $t$
We know that $I = 241.50$, $P = 1050$, and $t = 4$.
Step3: Calculate the interest rate
Substitute the values into the formula: $r=\frac{241.50}{1050\times4}=\frac{241.50}{4200}=0.0575$. To convert to a percentage, multiply by 100. So $r = 5.75%$.
Answer:
$5.75%$
5.
Explanation:
Step1: Recall simple - interest formula
The simple - interest formula for annual interest is $I = Pr$, where $I$ is the interest, $P$ is the principal amount, and $r$ is the annual interest rate.
Step2: Identify values of $P$ and $r$
We have $P = 410000$ and $r=0.0385$ (since $3.85%=0.0385$).
Step3: Calculate the annual interest
Substitute the values into the formula: $I = 410000\times0.0385 = 15785$.
Answer:
$$15785$
7.
Explanation:
Step1: Calculate the principal amount
Raj won $$900000$ and paid $$350000$ in taxes. So the principal amount $P$ he invested is $P=900000 - 350000=550000$.
Step2: Recall simple - interest formula
The simple - interest formula is $I = Prt$, where $t = 2$ years and $r = 0.0425$ (since $4.25%=0.0425$).
Step3: Calculate the interest
$I=Prt=550000\times0.0425\times2=550000\times0.085 = 46750$.
Step4: Calculate the total amount in the account
The total amount $A$ in the account is the sum of the principal and the interest, so $A=P + I=550000+46750 = 596750$.
Answer:
$$596750$