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) Donald took a loan of $7000 at the rate of 7% simple interest per annum. If he paid an amount of $11410 to clear the loan, then find the time period of the loan.
(2) Calculate the amount due if Karen borrowed a sum of $3950 at 3% simple interest for 4 years.
(3) Barbara took a loan of $5100 at the rate of 8% simple interest per annum. If he paid an amount of $8364 to clear the loan, then find the time period of the loan.
(4) What amount does Susan have to pay after 6 years if he takes a loan of $3650 at 2% simple interest?
(5) Matthew took a loan of $6400 at the rate of 8% simple interest per annum. If he paid an amount of $11008 to clear the loan, then find the time period of the loan.
(6) Joseph took a loan of $5400 at the rate of 8% simple interest per annum. If he paid an amount of $9720 to clear the loan, then find the time period of the loan.
(7) Lisa had to pay $4536 in order to furnish the loan taken 3 years before. If the rate of simple interest was 4% then find the sum borrowed.
(8) What amount will be due after 2 years if Thomas borrowed a sum of $3400 at a 6% simple interest?
(9) Betty took a loan of $6500 at the rate of 7% simple interest per annum. If he paid an amount of $10140 to clear the loan, then find the time period of the loan.
(10) What amount does Barbara have to pay after 6 years if he takes a loan of $3550 at 7% simple interest?