Question:
What amount does Susan have to pay after 6 years if he takes a loan of $3650 at 9% simple interest?
Correct Answer
$5621
Solution And Explanation
Solution
Given,
Principal (P) = $3650
Rate of Simple Interest (SI) = 9%
Time (t) = 6 years
Thus, Amount (A) = ?
The Rate of Interest is always calculated per annum, i.e. per year.
Thus, here 9% simple interest means, Rate of Simple Interest (SI) is 9% 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) = $3650 × 9% × 6
= $3650 ×9/100 × 6
= 3650 × 9 × 6/100
= 32850 × 6/100
= 197100/100
= $1971
Thus, Simple Interest = $1971
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 = $3650 + $1971
= $5621
Thus, Amount to be paid = $5621 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 = $3650
Rate of Simple Interest (SI) or (R) = 9%
And, Time (t) = 6 years
Thus, Amount (A)
= $3650 + ($3650 × 9% × 6)
= $3650 + ($3650 ×9/100 × 6)
= $3650 + (3650 × 9 × 6/100)
= $3650 + (32850 × 6/100)
= $3650 + (197100/100)
= $3650 + $1971 = $5621
Thus, Amount (A) to be paid = $5621 Answer
Method (3) Unitary Method
Calculation of Amount using Unitary Method
Calculation of Interest using Unitary Method
Here, given Rate of Simple Interest = 9%
This, means, $9 per $100 per year
∵ For $100, the simple interest for 1 year = $9
∴ For $1, the simple interest for 1 year = 9/100
∴ For $3650, the simple interest in 1 year
= 9/100 × 3650
= 9 × 3650/100
= 32850/100 = $328.5
Thus, simple interest for 1 year = $328.5
Therefore, simple interest for 6 years
= Simple interest for 1 year × 6
= $328.5 × 6 = $1971
Thus, Simple Interest (SI) = $1971
Calculation of Amount
Amount = Principal + Interest
Thus, Amount = $3650 + $1971
= $5621
Thus, Amount to be paid = $5621 Answer
Similar Questions
(1) Calculate the amount due after 9 years if Linda borrowed a sum of $5350 at a rate of 8% simple interest.
(2) Calculate the amount due after 10 years if Thomas borrowed a sum of $5800 at a rate of 9% simple interest.
(3) Calculate the amount due if Jessica borrowed a sum of $3750 at 5% simple interest for 4 years.
(4) James had to pay $3180 in order to furnish the loan taken 3 years before. If the rate of simple interest was 2% then find the sum borrowed.
(5) Calculate the amount due if Christopher borrowed a sum of $4000 at 8% simple interest for 4 years.
(6) Calculate the amount due if Patricia borrowed a sum of $3150 at 7% simple interest for 4 years.
(7) How much loan did George borrow 5 years ago at a rate of simple interest 5% per annum, if he paid $9125 to clear it?
(8) If William paid $4200 to settle his loan which he had taken 4 years before at a simple interest of 5%, then find the loan taken.
(9) Find the amount to be paid if Mary borrowed a sum of $5050 at 6% simple interest for 8 years.
(10) Michael had to pay $3597 in order to furnish the loan taken 3 years before. If the rate of simple interest was 3% then find the sum borrowed.