Question:
Calculate the amount due after 9 years if Christopher borrowed a sum of $6000 at a rate of 6% simple interest.
Correct Answer
$9240
Solution And Explanation
Solution
Given,
Principal (P) = $6000
Rate of Simple Interest (SI) = 6%
Time (t) = 9 years
Thus, Amount (A) = ?
The Rate of Interest is always calculated per annum, i.e. per year.
Thus, here 6% simple interest means, Rate of Simple Interest (SI) is 6% 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) = $6000 × 6% × 9
= $6000 ×6/100 × 9
= 6000 × 6 × 9/100
= 36000 × 9/100
= 324000/100
= $3240
Thus, Simple Interest = $3240
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 = $6000 + $3240
= $9240
Thus, Amount to be paid = $9240 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 = $6000
Rate of Simple Interest (SI) or (R) = 6%
And, Time (t) = 9 years
Thus, Amount (A)
= $6000 + ($6000 × 6% × 9)
= $6000 + ($6000 ×6/100 × 9)
= $6000 + (6000 × 6 × 9/100)
= $6000 + (36000 × 9/100)
= $6000 + (324000/100)
= $6000 + $3240 = $9240
Thus, Amount (A) to be paid = $9240 Answer
Method (3) Unitary Method
Calculation of Amount using Unitary Method
Calculation of Interest using Unitary Method
Here, given Rate of Simple Interest = 6%
This, means, $6 per $100 per year
∵ For $100, the simple interest for 1 year = $6
∴ For $1, the simple interest for 1 year = 6/100
∴ For $6000, the simple interest in 1 year
= 6/100 × 6000
= 6 × 6000/100
= 36000/100 = $360
Thus, simple interest for 1 year = $360
Therefore, simple interest for 9 years
= Simple interest for 1 year × 9
= $360 × 9 = $3240
Thus, Simple Interest (SI) = $3240
Calculation of Amount
Amount = Principal + Interest
Thus, Amount = $6000 + $3240
= $9240
Thus, Amount to be paid = $9240 Answer
Similar Questions
(1) Calculate the amount due if Karen borrowed a sum of $3950 at 9% simple interest for 3 years.
(2) Calculate the amount due if Elizabeth borrowed a sum of $3450 at 10% simple interest for 4 years.
(3) Calculate the amount due after 9 years if Thomas borrowed a sum of $5800 at a rate of 5% simple interest.
(4) What amount does Jessica have to pay after 5 years if he takes a loan of $3750 at 3% simple interest?
(5) Calculate the amount due after 10 years if Sarah borrowed a sum of $5850 at a rate of 10% simple interest.
(6) What amount does Charles have to pay after 5 years if he takes a loan of $3900 at 2% simple interest?
(7) Jennifer took a loan of $4500 at the rate of 10% simple interest per annum. If he paid an amount of $7200 to clear the loan, then find the time period of the loan.
(8) If Richard paid $4320 to settle his loan which he had taken 4 years before at a simple interest of 5%, then find the loan taken.
(9) Calculate the amount due if Jessica borrowed a sum of $3750 at 7% simple interest for 3 years.
(10) What amount will be due after 2 years if Daniel borrowed a sum of $3550 at a 5% simple interest?