Question:
Find the amount to be paid if Thomas borrowed a sum of $5800 at 9% simple interest for 7 years.
Correct Answer
$9454
Solution And Explanation
Solution
Given,
Principal (P) = $5800
Rate of Simple Interest (SI) = 9%
Time (t) = 7 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) = $5800 × 9% × 7
= $5800 ×9/100 × 7
= 5800 × 9 × 7/100
= 52200 × 7/100
= 365400/100
= $3654
Thus, Simple Interest = $3654
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 = $5800 + $3654
= $9454
Thus, Amount to be paid = $9454 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 = $5800
Rate of Simple Interest (SI) or (R) = 9%
And, Time (t) = 7 years
Thus, Amount (A)
= $5800 + ($5800 × 9% × 7)
= $5800 + ($5800 ×9/100 × 7)
= $5800 + (5800 × 9 × 7/100)
= $5800 + (52200 × 7/100)
= $5800 + (365400/100)
= $5800 + $3654 = $9454
Thus, Amount (A) to be paid = $9454 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 $5800, the simple interest in 1 year
= 9/100 × 5800
= 9 × 5800/100
= 52200/100 = $522
Thus, simple interest for 1 year = $522
Therefore, simple interest for 7 years
= Simple interest for 1 year × 7
= $522 × 7 = $3654
Thus, Simple Interest (SI) = $3654
Calculation of Amount
Amount = Principal + Interest
Thus, Amount = $5800 + $3654
= $9454
Thus, Amount to be paid = $9454 Answer
Similar Questions
(1) Calculate the amount due if Barbara borrowed a sum of $3550 at 6% simple interest for 4 years.
(2) Calculate the amount due after 10 years if Christopher borrowed a sum of $6000 at a rate of 5% simple interest.
(3) Find the amount to be paid if William borrowed a sum of $5500 at 6% simple interest for 8 years.
(4) Calculate the amount due if Charles borrowed a sum of $3900 at 5% simple interest for 3 years.
(5) Calculate the amount due if Sarah borrowed a sum of $3850 at 9% simple interest for 4 years.
(6) Find the amount to be paid if Elizabeth borrowed a sum of $5450 at 5% simple interest for 8 years.
(7) Patricia took a loan of $4300 at the rate of 6% simple interest per annum. If he paid an amount of $5848 to clear the loan, then find the time period of the loan.
(8) Jennifer took a loan of $4500 at the rate of 8% simple interest per annum. If he paid an amount of $7380 to clear the loan, then find the time period of the loan.
(9) David took a loan of $4800 at the rate of 9% simple interest per annum. If he paid an amount of $9120 to clear the loan, then find the time period of the loan.
(10) How much loan did Jason borrow 5 years ago at a rate of simple interest 4% per annum, if he paid $9240 to clear it?