Question:
Calculate the amount due if Jessica borrowed a sum of $3750 at 9% simple interest for 4 years.
Correct Answer
$5100
Solution And Explanation
Solution
Given,
Principal (P) = $3750
Rate of Simple Interest (SI) = 9%
Time (t) = 4 years
Thus, Amount (A) = ?
The Rate of Interest is always calculated per annum, i.e. per year.
Thus, here 9% simple interest means, Rate of Simple Interest (SI) is 9% 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) = $3750 × 9% × 4
= $3750 ×9/100 × 4
= 3750 × 9 × 4/100
= 33750 × 4/100
= 135000/100
= $1350
Thus, Simple Interest = $1350
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 = $3750 + $1350
= $5100
Thus, Amount to be paid = $5100 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 = $3750
Rate of Simple Interest (SI) or (R) = 9%
And, Time (t) = 4 years
Thus, Amount (A)
= $3750 + ($3750 × 9% × 4)
= $3750 + ($3750 ×9/100 × 4)
= $3750 + (3750 × 9 × 4/100)
= $3750 + (33750 × 4/100)
= $3750 + (135000/100)
= $3750 + $1350 = $5100
Thus, Amount (A) to be paid = $5100 Answer
Method (3) Unitary Method
Calculation of Amount using Unitary Method
Calculation of Interest using Unitary Method
Here, given Rate of Simple Interest = 9%
This, means, $9 per $100 per year
∵ For $100, the simple interest for 1 year = $9
∴ For $1, the simple interest for 1 year = 9/100
∴ For $3750, the simple interest in 1 year
= 9/100 × 3750
= 9 × 3750/100
= 33750/100 = $337.5
Thus, simple interest for 1 year = $337.5
Therefore, simple interest for 4 years
= Simple interest for 1 year × 4
= $337.5 × 4 = $1350
Thus, Simple Interest (SI) = $1350
Calculation of Amount
Amount = Principal + Interest
Thus, Amount = $3750 + $1350
= $5100
Thus, Amount to be paid = $5100 Answer
Similar Questions
(1) David took a loan of $4800 at the rate of 9% simple interest per annum. If he paid an amount of $8256 to clear the loan, then find the time period of the loan.
(2) What amount does Michael have to pay after 5 years if he takes a loan of $3300 at 3% simple interest?
(3) Calculate the amount due after 9 years if Patricia borrowed a sum of $5150 at a rate of 5% simple interest.
(4) Susan took a loan of $5300 at the rate of 7% simple interest per annum. If he paid an amount of $7526 to clear the loan, then find the time period of the loan.
(5) Karen took a loan of $5900 at the rate of 8% simple interest per annum. If he paid an amount of $10148 to clear the loan, then find the time period of the loan.
(6) Matthew took a loan of $6400 at the rate of 10% simple interest per annum. If he paid an amount of $10240 to clear the loan, then find the time period of the loan.
(7) Margaret took a loan of $6700 at the rate of 7% simple interest per annum. If he paid an amount of $10452 to clear the loan, then find the time period of the loan.
(8) Calculate the amount due if Christopher borrowed a sum of $4000 at 4% simple interest for 3 years.
(9) If Patricia paid $3654 to settle his loan which he had taken 4 years before at a simple interest of 4%, then find the loan taken.
(10) What amount does Jessica have to pay after 6 years if he takes a loan of $3750 at 8% simple interest?