Question:
Calculate the amount due after 9 years if Thomas borrowed a sum of $5800 at a rate of 5% simple interest.
Correct Answer
$8410
Solution And Explanation
Solution
Given,
Principal (P) = $5800
Rate of Simple Interest (SI) = 5%
Time (t) = 9 years
Thus, Amount (A) = ?
The Rate of Interest is always calculated per annum, i.e. per year.
Thus, here 5% simple interest means, Rate of Simple Interest (SI) is 5% 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) = $5800 × 5% × 9
= $5800 ×5/100 × 9
= 5800 × 5 × 9/100
= 29000 × 9/100
= 261000/100
= $2610
Thus, Simple Interest = $2610
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 = $5800 + $2610
= $8410
Thus, Amount to be paid = $8410 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 = $5800
Rate of Simple Interest (SI) or (R) = 5%
And, Time (t) = 9 years
Thus, Amount (A)
= $5800 + ($5800 × 5% × 9)
= $5800 + ($5800 ×5/100 × 9)
= $5800 + (5800 × 5 × 9/100)
= $5800 + (29000 × 9/100)
= $5800 + (261000/100)
= $5800 + $2610 = $8410
Thus, Amount (A) to be paid = $8410 Answer
Method (3) Unitary Method
Calculation of Amount using Unitary Method
Calculation of Interest using Unitary Method
Here, given Rate of Simple Interest = 5%
This, means, $5 per $100 per year
∵ For $100, the simple interest for 1 year = $5
∴ For $1, the simple interest for 1 year = 5/100
∴ For $5800, the simple interest in 1 year
= 5/100 × 5800
= 5 × 5800/100
= 29000/100 = $290
Thus, simple interest for 1 year = $290
Therefore, simple interest for 9 years
= Simple interest for 1 year × 9
= $290 × 9 = $2610
Thus, Simple Interest (SI) = $2610
Calculation of Amount
Amount = Principal + Interest
Thus, Amount = $5800 + $2610
= $8410
Thus, Amount to be paid = $8410 Answer
Similar Questions
(1) Calculate the amount due after 9 years if William borrowed a sum of $5500 at a rate of 2% simple interest.
(2) How much loan did Margaret borrow 5 years ago at a rate of simple interest 5% per annum, if he paid $7937.5 to clear it?
(3) What amount does Richard have to pay after 5 years if he takes a loan of $3600 at 4% simple interest?
(4) If Thomas borrowed $3800 from a bank at a rate of 3% simple interest per annum then find the amount to be paid after 2 years.
(5) Karen took a loan of $5900 at the rate of 7% simple interest per annum. If he paid an amount of $10030 to clear the loan, then find the time period of the loan.
(6) Calculate the amount due if Barbara borrowed a sum of $3550 at 5% simple interest for 3 years.
(7) Calculate the amount due after 10 years if William borrowed a sum of $5500 at a rate of 5% simple interest.
(8) Calculate the amount due after 9 years if Barbara borrowed a sum of $5550 at a rate of 2% simple interest.
(9) How much loan did Joshua borrow 5 years ago at a rate of simple interest 4% per annum, if he paid $8280 to clear it?
(10) If Michael borrowed $3300 from a bank at a rate of 3% simple interest per annum then find the amount to be paid after 2 years.