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 after 9 years if Robert borrowed a sum of $5100 at a rate of 9% simple interest.
(2) What amount will be due after 2 years if Joshua borrowed a sum of $3950 at a 6% simple interest?
(3) How much loan did Kevin borrow 5 years ago at a rate of simple interest 2% per annum, if he paid $7810 to clear it?
(4) If Jessica borrowed $3750 from a bank at a rate of 3% simple interest per annum then find the amount to be paid after 2 years.
(5) What amount does John have to pay after 6 years if he takes a loan of $3200 at 3% simple interest?
(6) Mark took a loan of $6800 at the rate of 8% simple interest per annum. If he paid an amount of $12240 to clear the loan, then find the time period of the loan.
(7) Michael took a loan of $4600 at the rate of 9% simple interest per annum. If he paid an amount of $7912 to clear the loan, then find the time period of the loan.
(8) If Michelle paid $5346 to settle his loan which he had taken 4 years before at a simple interest of 2%, then find the loan taken.
(9) What amount does Joseph have to pay after 6 years if he takes a loan of $3700 at 4% simple interest?
(10) What amount does Joseph have to pay after 6 years if he takes a loan of $3700 at 6% simple interest?