Question:
Calculate the amount due after 9 years if John borrowed a sum of $5200 at a rate of 2% simple interest.
Correct Answer
$6136
Solution And Explanation
Solution
Given,
Principal (P) = $5200
Rate of Simple Interest (SI) = 2%
Time (t) = 9 years
Thus, Amount (A) = ?
The Rate of Interest is always calculated per annum, i.e. per year.
Thus, here 2% simple interest means, Rate of Simple Interest (SI) is 2% 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) = $5200 × 2% × 9
= $5200 ×2/100 × 9
= 5200 × 2 × 9/100
= 10400 × 9/100
= 93600/100
= $936
Thus, Simple Interest = $936
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 = $5200 + $936
= $6136
Thus, Amount to be paid = $6136 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 = $5200
Rate of Simple Interest (SI) or (R) = 2%
And, Time (t) = 9 years
Thus, Amount (A)
= $5200 + ($5200 × 2% × 9)
= $5200 + ($5200 ×2/100 × 9)
= $5200 + (5200 × 2 × 9/100)
= $5200 + (10400 × 9/100)
= $5200 + (93600/100)
= $5200 + $936 = $6136
Thus, Amount (A) to be paid = $6136 Answer
Method (3) Unitary Method
Calculation of Amount using Unitary Method
Calculation of Interest using Unitary Method
Here, given Rate of Simple Interest = 2%
This, means, $2 per $100 per year
∵ For $100, the simple interest for 1 year = $2
∴ For $1, the simple interest for 1 year = 2/100
∴ For $5200, the simple interest in 1 year
= 2/100 × 5200
= 2 × 5200/100
= 10400/100 = $104
Thus, simple interest for 1 year = $104
Therefore, simple interest for 9 years
= Simple interest for 1 year × 9
= $104 × 9 = $936
Thus, Simple Interest (SI) = $936
Calculation of Amount
Amount = Principal + Interest
Thus, Amount = $5200 + $936
= $6136
Thus, Amount to be paid = $6136 Answer
Similar Questions
(1) What amount does Karen have to pay after 5 years if he takes a loan of $3950 at 4% simple interest?
(2) How much loan did Carol borrow 5 years ago at a rate of simple interest 2% per annum, if he paid $7755 to clear it?
(3) Find the amount to be paid if David borrowed a sum of $5400 at 5% simple interest for 7 years.
(4) Find the amount to be paid if Elizabeth borrowed a sum of $5450 at 6% simple interest for 7 years.
(5) Calculate the amount due after 10 years if Christopher borrowed a sum of $6000 at a rate of 6% simple interest.
(6) What amount does Thomas have to pay after 5 years if he takes a loan of $3800 at 5% simple interest?
(7) Calculate the amount due if Christopher borrowed a sum of $4000 at 6% simple interest for 3 years.
(8) Sarah took a loan of $5700 at the rate of 9% simple interest per annum. If he paid an amount of $8778 to clear the loan, then find the time period of the loan.
(9) Calculate the amount due after 9 years if Richard borrowed a sum of $5600 at a rate of 4% simple interest.
(10) John took a loan of $4400 at the rate of 9% simple interest per annum. If he paid an amount of $7964 to clear the loan, then find the time period of the loan.