Question:
Calculate the amount due after 9 years if Jennifer borrowed a sum of $5250 at a rate of 10% simple interest.
Correct Answer
$9975
Solution And Explanation
Solution
Given,
Principal (P) = $5250
Rate of Simple Interest (SI) = 10%
Time (t) = 9 years
Thus, Amount (A) = ?
The Rate of Interest is always calculated per annum, i.e. per year.
Thus, here 10% simple interest means, Rate of Simple Interest (SI) is 10% per annum.
Method (1) Using Formula
Calculation of Simple Interest
Formula to Calculate Simple Interest
Simple Interest (SI) = Principal × Rate × Time
Thus, Simple Interest (SI) = $5250 × 10% × 9
= $5250 ×10/100 × 9
= 5250 × 10 × 9/100
= 52500 × 9/100
= 472500/100
= $4725
Thus, Simple Interest = $4725
Calculation of Amount
The total money paid to the lender by a borrower is called the Amount.
In other words, sum of priciple and interest is called the Amount.
Formula to Calculate the Amount
Amount = Principal + Interest
Thus, Amount = $5250 + $4725
= $9975
Thus, Amount to be paid = $9975 Answer
Method (2)
Calculation of Amount when Principal, Rate of Simple Interest and Time are given
Calculation of Amount directly using Principal, SI, and Time
Formula to calculate the Amount
Amount (A) = Principal (P) + Principal(P) × Rate of Interest (SI) × Time (t)
⇒ A = P + PRT
Here in the question, P = $5250
Rate of Simple Interest (SI) or (R) = 10%
And, Time (t) = 9 years
Thus, Amount (A)
= $5250 + ($5250 × 10% × 9)
= $5250 + ($5250 ×10/100 × 9)
= $5250 + (5250 × 10 × 9/100)
= $5250 + (52500 × 9/100)
= $5250 + (472500/100)
= $5250 + $4725 = $9975
Thus, Amount (A) to be paid = $9975 Answer
Method (3) Unitary Method
Calculation of Amount using Unitary Method
Calculation of Interest using Unitary Method
Here, given Rate of Simple Interest = 10%
This, means, $10 per $100 per year
∵ For $100, the simple interest for 1 year = $10
∴ For $1, the simple interest for 1 year = 10/100
∴ For $5250, the simple interest in 1 year
= 10/100 × 5250
= 10 × 5250/100
= 52500/100 = $525
Thus, simple interest for 1 year = $525
Therefore, simple interest for 9 years
= Simple interest for 1 year × 9
= $525 × 9 = $4725
Thus, Simple Interest (SI) = $4725
Calculation of Amount
Amount = Principal + Interest
Thus, Amount = $5250 + $4725
= $9975
Thus, Amount to be paid = $9975 Answer
Similar Questions
(1) Calculate the amount due after 9 years if Charles borrowed a sum of $5900 at a rate of 5% simple interest.
(2) What amount will be due after 2 years if Thomas borrowed a sum of $3400 at a 9% simple interest?
(3) Calculate the amount due if Charles borrowed a sum of $3900 at 3% simple interest for 4 years.
(4) If Christopher paid $4640 to settle his loan which he had taken 4 years before at a simple interest of 4%, then find the loan taken.
(5) Find the amount to be paid if Thomas borrowed a sum of $5800 at 2% simple interest for 8 years.
(6) Margaret took a loan of $6700 at the rate of 6% simple interest per annum. If he paid an amount of $9916 to clear the loan, then find the time period of the loan.
(7) Joseph took a loan of $5400 at the rate of 10% simple interest per annum. If he paid an amount of $10800 to clear the loan, then find the time period of the loan.
(8) William took a loan of $5000 at the rate of 9% simple interest per annum. If he paid an amount of $7700 to clear the loan, then find the time period of the loan.
(9) What amount does Mary have to pay after 5 years if he takes a loan of $3050 at 5% simple interest?
(10) Calculate the amount due after 9 years if Karen borrowed a sum of $5950 at a rate of 10% simple interest.