Question:
Calculate the amount due if Richard borrowed a sum of $3600 at 8% simple interest for 3 years.
Correct Answer
$4464
Solution And Explanation
Solution
Given,
Principal (P) = $3600
Rate of Simple Interest (SI) = 8%
Time (t) = 3 years
Thus, Amount (A) = ?
The Rate of Interest is always calculated per annum, i.e. per year.
Thus, here 8% simple interest means, Rate of Simple Interest (SI) is 8% 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) = $3600 × 8% × 3
= $3600 ×8/100 × 3
= 3600 × 8 × 3/100
= 28800 × 3/100
= 86400/100
= $864
Thus, Simple Interest = $864
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 = $3600 + $864
= $4464
Thus, Amount to be paid = $4464 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 = $3600
Rate of Simple Interest (SI) or (R) = 8%
And, Time (t) = 3 years
Thus, Amount (A)
= $3600 + ($3600 × 8% × 3)
= $3600 + ($3600 ×8/100 × 3)
= $3600 + (3600 × 8 × 3/100)
= $3600 + (28800 × 3/100)
= $3600 + (86400/100)
= $3600 + $864 = $4464
Thus, Amount (A) to be paid = $4464 Answer
Method (3) Unitary Method
Calculation of Amount using Unitary Method
Calculation of Interest using Unitary Method
Here, given Rate of Simple Interest = 8%
This, means, $8 per $100 per year
∵ For $100, the simple interest for 1 year = $8
∴ For $1, the simple interest for 1 year = 8/100
∴ For $3600, the simple interest in 1 year
= 8/100 × 3600
= 8 × 3600/100
= 28800/100 = $288
Thus, simple interest for 1 year = $288
Therefore, simple interest for 3 years
= Simple interest for 1 year × 3
= $288 × 3 = $864
Thus, Simple Interest (SI) = $864
Calculation of Amount
Amount = Principal + Interest
Thus, Amount = $3600 + $864
= $4464
Thus, Amount to be paid = $4464 Answer
Similar Questions
(1) Calculate the amount due if David borrowed a sum of $3400 at 3% simple interest for 4 years.
(2) Charles had to pay $4368 in order to furnish the loan taken 3 years before. If the rate of simple interest was 4% then find the sum borrowed.
(3) Find the amount to be paid if Jessica borrowed a sum of $5750 at 5% simple interest for 8 years.
(4) Nancy took a loan of $6300 at the rate of 9% simple interest per annum. If he paid an amount of $9702 to clear the loan, then find the time period of the loan.
(5) Find the amount to be paid if Charles borrowed a sum of $5900 at 6% simple interest for 7 years.
(6) Calculate the amount due after 9 years if Jennifer borrowed a sum of $5250 at a rate of 4% simple interest.
(7) How much loan did Nancy borrow 5 years ago at a rate of simple interest 4% per annum, if he paid $7380 to clear it?
(8) If Susan paid $4380 to settle his loan which he had taken 4 years before at a simple interest of 5%, then find the loan taken.
(9) What amount does Linda have to pay after 6 years if he takes a loan of $3350 at 6% simple interest?
(10) Mary took a loan of $4100 at the rate of 10% simple interest per annum. If he paid an amount of $7380 to clear the loan, then find the time period of the loan.