Question:
Calculate the amount due after 10 years if Charles borrowed a sum of $5900 at a rate of 9% simple interest.
Correct Answer
$11210
Solution And Explanation
Solution
Given,
Principal (P) = $5900
Rate of Simple Interest (SI) = 9%
Time (t) = 10 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) = $5900 × 9% × 10
= $5900 ×9/100 × 10
= 5900 × 9 × 10/100
= 53100 × 10/100
= 531000/100
= $5310
Thus, Simple Interest = $5310
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 = $5900 + $5310
= $11210
Thus, Amount to be paid = $11210 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 = $5900
Rate of Simple Interest (SI) or (R) = 9%
And, Time (t) = 10 years
Thus, Amount (A)
= $5900 + ($5900 × 9% × 10)
= $5900 + ($5900 ×9/100 × 10)
= $5900 + (5900 × 9 × 10/100)
= $5900 + (53100 × 10/100)
= $5900 + (531000/100)
= $5900 + $5310 = $11210
Thus, Amount (A) to be paid = $11210 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 $5900, the simple interest in 1 year
= 9/100 × 5900
= 9 × 5900/100
= 53100/100 = $531
Thus, simple interest for 1 year = $531
Therefore, simple interest for 10 years
= Simple interest for 1 year × 10
= $531 × 10 = $5310
Thus, Simple Interest (SI) = $5310
Calculation of Amount
Amount = Principal + Interest
Thus, Amount = $5900 + $5310
= $11210
Thus, Amount to be paid = $11210 Answer
Similar Questions
(1) Calculate the amount due after 9 years if William borrowed a sum of $5500 at a rate of 5% simple interest.
(2) Find the amount to be paid if Karen borrowed a sum of $5950 at 3% simple interest for 8 years.
(3) What amount does David have to pay after 5 years if he takes a loan of $3400 at 10% simple interest?
(4) David took a loan of $4800 at the rate of 9% simple interest per annum. If he paid an amount of $7392 to clear the loan, then find the time period of the loan.
(5) Barbara took a loan of $5100 at the rate of 10% simple interest per annum. If he paid an amount of $8670 to clear the loan, then find the time period of the loan.
(6) William took a loan of $5000 at the rate of 10% simple interest per annum. If he paid an amount of $10000 to clear the loan, then find the time period of the loan.
(7) Calculate the amount due after 9 years if Jennifer borrowed a sum of $5250 at a rate of 6% simple interest.
(8) In how much time a principal of $3200 will amount to $3520 at a simple interest of 5% per annum?
(9) Patricia took a loan of $4300 at the rate of 7% simple interest per annum. If he paid an amount of $6407 to clear the loan, then find the time period of the loan.
(10) Patricia took a loan of $4300 at the rate of 9% simple interest per annum. If he paid an amount of $7009 to clear the loan, then find the time period of the loan.