Question:
Calculate the amount due after 9 years if Michael borrowed a sum of $5300 at a rate of 3% simple interest.
Correct Answer
$6731
Solution And Explanation
Solution
Given,
Principal (P) = $5300
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) = $5300 × 3% × 9
= $5300 ×3/100 × 9
= 5300 × 3 × 9/100
= 15900 × 9/100
= 143100/100
= $1431
Thus, Simple Interest = $1431
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 = $5300 + $1431
= $6731
Thus, Amount to be paid = $6731 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 = $5300
Rate of Simple Interest (SI) or (R) = 3%
And, Time (t) = 9 years
Thus, Amount (A)
= $5300 + ($5300 × 3% × 9)
= $5300 + ($5300 ×3/100 × 9)
= $5300 + (5300 × 3 × 9/100)
= $5300 + (15900 × 9/100)
= $5300 + (143100/100)
= $5300 + $1431 = $6731
Thus, Amount (A) to be paid = $6731 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 $5300, the simple interest in 1 year
= 3/100 × 5300
= 3 × 5300/100
= 15900/100 = $159
Thus, simple interest for 1 year = $159
Therefore, simple interest for 9 years
= Simple interest for 1 year × 9
= $159 × 9 = $1431
Thus, Simple Interest (SI) = $1431
Calculation of Amount
Amount = Principal + Interest
Thus, Amount = $5300 + $1431
= $6731
Thus, Amount to be paid = $6731 Answer
Similar Questions
(1) Joshua had to pay $5635 in order to furnish the loan taken 3 years before. If the rate of simple interest was 5% then find the sum borrowed.
(2) Find the amount to be paid if Richard borrowed a sum of $5600 at 2% simple interest for 8 years.
(3) What amount does Susan have to pay after 6 years if he takes a loan of $3650 at 9% simple interest?
(4) Calculate the amount due after 9 years if Susan borrowed a sum of $5650 at a rate of 4% simple interest.
(5) Find the amount to be paid if Sarah borrowed a sum of $5850 at 10% simple interest for 8 years.
(6) Calculate the amount due if William borrowed a sum of $3500 at 10% simple interest for 4 years.
(7) How much loan did Kevin borrow 5 years ago at a rate of simple interest 3% per annum, if he paid $8165 to clear it?
(8) Calculate the amount due if Karen borrowed a sum of $3950 at 5% simple interest for 4 years.
(9) Find the amount to be paid if Michael borrowed a sum of $5300 at 10% simple interest for 8 years.
(10) How much loan did William borrow 5 years ago at a rate of simple interest 2% per annum, if he paid $6050 to clear it?