Question:
What amount does Charles have to pay after 6 years if he takes a loan of $3900 at 8% simple interest?
Correct Answer
$5772
Solution And Explanation
Solution
Given,
Principal (P) = $3900
Rate of Simple Interest (SI) = 8%
Time (t) = 6 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) = $3900 × 8% × 6
= $3900 ×8/100 × 6
= 3900 × 8 × 6/100
= 31200 × 6/100
= 187200/100
= $1872
Thus, Simple Interest = $1872
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 = $3900 + $1872
= $5772
Thus, Amount to be paid = $5772 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 = $3900
Rate of Simple Interest (SI) or (R) = 8%
And, Time (t) = 6 years
Thus, Amount (A)
= $3900 + ($3900 × 8% × 6)
= $3900 + ($3900 ×8/100 × 6)
= $3900 + (3900 × 8 × 6/100)
= $3900 + (31200 × 6/100)
= $3900 + (187200/100)
= $3900 + $1872 = $5772
Thus, Amount (A) to be paid = $5772 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 $3900, the simple interest in 1 year
= 8/100 × 3900
= 8 × 3900/100
= 31200/100 = $312
Thus, simple interest for 1 year = $312
Therefore, simple interest for 6 years
= Simple interest for 1 year × 6
= $312 × 6 = $1872
Thus, Simple Interest (SI) = $1872
Calculation of Amount
Amount = Principal + Interest
Thus, Amount = $3900 + $1872
= $5772
Thus, Amount to be paid = $5772 Answer
Similar Questions
(1) Find the amount to be paid if Barbara borrowed a sum of $5550 at 3% simple interest for 7 years.
(2) Karen took a loan of $5900 at the rate of 9% simple interest per annum. If he paid an amount of $10148 to clear the loan, then find the time period of the loan.
(3) Calculate the amount due if William borrowed a sum of $3500 at 5% simple interest for 3 years.
(4) Karen took a loan of $5900 at the rate of 6% simple interest per annum. If he paid an amount of $8378 to clear the loan, then find the time period of the loan.
(5) What amount does Robert have to pay after 6 years if he takes a loan of $3100 at 5% simple interest?
(6) Lisa took a loan of $6100 at the rate of 10% simple interest per annum. If he paid an amount of $11590 to clear the loan, then find the time period of the loan.
(7) Calculate the amount due after 10 years if David borrowed a sum of $5400 at a rate of 2% simple interest.
(8) What amount will be due after 2 years if Daniel borrowed a sum of $3550 at a 7% simple interest?
(9) Find the amount to be paid if Linda borrowed a sum of $5350 at 2% simple interest for 7 years.
(10) If Karen borrowed $3950 from a bank at a rate of 2% simple interest per annum then find the amount to be paid after 2 years.