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) In how much time a principal of $3100 will amount to $3720 at a simple interest of 4% per annum?
(2) Find the amount to be paid if Susan borrowed a sum of $5650 at 4% simple interest for 7 years.
(3) If Christopher borrowed $4000 from a bank at a rate of 2% simple interest per annum then find the amount to be paid after 2 years.
(4) Find the amount to be paid if Charles borrowed a sum of $5900 at 3% simple interest for 8 years.
(5) Calculate the amount due after 10 years if Karen borrowed a sum of $5950 at a rate of 8% simple interest.
(6) Find the amount to be paid if Sarah borrowed a sum of $5850 at 6% simple interest for 7 years.
(7) Calculate the amount due after 10 years if Susan borrowed a sum of $5650 at a rate of 8% simple interest.
(8) Elizabeth took a loan of $4900 at the rate of 6% simple interest per annum. If he paid an amount of $7546 to clear the loan, then find the time period of the loan.
(9) Robert took a loan of $4200 at the rate of 8% simple interest per annum. If he paid an amount of $6216 to clear the loan, then find the time period of the loan.
(10) If Linda paid $3752 to settle his loan which he had taken 4 years before at a simple interest of 3%, then find the loan taken.