Question:
Find the amount to be paid if Jennifer borrowed a sum of $5250 at 7% simple interest for 8 years.
Correct Answer
$8190
Solution And Explanation
Solution
Given,
Principal (P) = $5250
Rate of Simple Interest (SI) = 7%
Time (t) = 8 years
Thus, Amount (A) = ?
The Rate of Interest is always calculated per annum, i.e. per year.
Thus, here 7% simple interest means, Rate of Simple Interest (SI) is 7% 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 × 7% × 8
= $5250 ×7/100 × 8
= 5250 × 7 × 8/100
= 36750 × 8/100
= 294000/100
= $2940
Thus, Simple Interest = $2940
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 + $2940
= $8190
Thus, Amount to be paid = $8190 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) = 7%
And, Time (t) = 8 years
Thus, Amount (A)
= $5250 + ($5250 × 7% × 8)
= $5250 + ($5250 ×7/100 × 8)
= $5250 + (5250 × 7 × 8/100)
= $5250 + (36750 × 8/100)
= $5250 + (294000/100)
= $5250 + $2940 = $8190
Thus, Amount (A) to be paid = $8190 Answer
Method (3) Unitary Method
Calculation of Amount using Unitary Method
Calculation of Interest using Unitary Method
Here, given Rate of Simple Interest = 7%
This, means, $7 per $100 per year
∵ For $100, the simple interest for 1 year = $7
∴ For $1, the simple interest for 1 year = 7/100
∴ For $5250, the simple interest in 1 year
= 7/100 × 5250
= 7 × 5250/100
= 36750/100 = $367.5
Thus, simple interest for 1 year = $367.5
Therefore, simple interest for 8 years
= Simple interest for 1 year × 8
= $367.5 × 8 = $2940
Thus, Simple Interest (SI) = $2940
Calculation of Amount
Amount = Principal + Interest
Thus, Amount = $5250 + $2940
= $8190
Thus, Amount to be paid = $8190 Answer
Similar Questions
(1) Karen took a loan of $5900 at the rate of 6% simple interest per annum. If he paid an amount of $9440 to clear the loan, then find the time period of the loan.
(2) Charles took a loan of $5800 at the rate of 8% simple interest per annum. If he paid an amount of $9976 to clear the loan, then find the time period of the loan.
(3) Calculate the amount due if William borrowed a sum of $3500 at 7% simple interest for 3 years.
(4) Mary had to pay $3324.5 in order to furnish the loan taken 3 years before. If the rate of simple interest was 3% then find the sum borrowed.
(5) Calculate the amount due after 10 years if Jessica borrowed a sum of $5750 at a rate of 9% simple interest.
(6) How much loan did Mark borrow 5 years ago at a rate of simple interest 2% per annum, if he paid $7040 to clear it?
(7) Calculate the amount due if Barbara borrowed a sum of $3550 at 10% simple interest for 4 years.
(8) Find the amount to be paid if Karen borrowed a sum of $5950 at 4% simple interest for 8 years.
(9) Find the amount to be paid if Jessica borrowed a sum of $5750 at 4% simple interest for 8 years.
(10) Calculate the amount due after 9 years if Susan borrowed a sum of $5650 at a rate of 5% simple interest.