Question:
Calculate the amount due after 9 years if Thomas borrowed a sum of $5800 at a rate of 3% simple interest.
Correct Answer
$7366
Solution And Explanation
Solution
Given,
Principal (P) = $5800
Rate of Simple Interest (SI) = 3%
Time (t) = 9 years
Thus, Amount (A) = ?
The Rate of Interest is always calculated per annum, i.e. per year.
Thus, here 3% simple interest means, Rate of Simple Interest (SI) is 3% 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 × 3% × 9
= $5800 ×3/100 × 9
= 5800 × 3 × 9/100
= 17400 × 9/100
= 156600/100
= $1566
Thus, Simple Interest = $1566
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 + $1566
= $7366
Thus, Amount to be paid = $7366 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) = 3%
And, Time (t) = 9 years
Thus, Amount (A)
= $5800 + ($5800 × 3% × 9)
= $5800 + ($5800 ×3/100 × 9)
= $5800 + (5800 × 3 × 9/100)
= $5800 + (17400 × 9/100)
= $5800 + (156600/100)
= $5800 + $1566 = $7366
Thus, Amount (A) to be paid = $7366 Answer
Method (3) Unitary Method
Calculation of Amount using Unitary Method
Calculation of Interest using Unitary Method
Here, given Rate of Simple Interest = 3%
This, means, $3 per $100 per year
∵ For $100, the simple interest for 1 year = $3
∴ For $1, the simple interest for 1 year = 3/100
∴ For $5800, the simple interest in 1 year
= 3/100 × 5800
= 3 × 5800/100
= 17400/100 = $174
Thus, simple interest for 1 year = $174
Therefore, simple interest for 9 years
= Simple interest for 1 year × 9
= $174 × 9 = $1566
Thus, Simple Interest (SI) = $1566
Calculation of Amount
Amount = Principal + Interest
Thus, Amount = $5800 + $1566
= $7366
Thus, Amount to be paid = $7366 Answer
Similar Questions
(1) What amount does Sarah have to pay after 5 years if he takes a loan of $3850 at 6% simple interest?
(2) Calculate the amount due if Linda borrowed a sum of $3350 at 2% simple interest for 4 years.
(3) Calculate the amount due after 9 years if Christopher borrowed a sum of $6000 at a rate of 8% simple interest.
(4) Sandra took a loan of $6900 at the rate of 8% simple interest per annum. If he paid an amount of $11868 to clear the loan, then find the time period of the loan.
(5) Calculate the amount due after 9 years if Susan borrowed a sum of $5650 at a rate of 6% simple interest.
(6) Calculate the amount due if Karen borrowed a sum of $3950 at 2% simple interest for 3 years.
(7) How much loan did Sandra borrow 5 years ago at a rate of simple interest 4% per annum, if he paid $7740 to clear it?
(8) If Karen paid $4424 to settle his loan which he had taken 4 years before at a simple interest of 3%, then find the loan taken.
(9) Find the amount to be paid if Karen borrowed a sum of $5950 at 5% simple interest for 7 years.
(10) Calculate the amount due if Jessica borrowed a sum of $3750 at 2% simple interest for 4 years.