Question:
Calculate the amount due after 9 years if Linda borrowed a sum of $5350 at a rate of 2% simple interest.
Correct Answer
$6313
Solution And Explanation
Solution
Given,
Principal (P) = $5350
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) = $5350 × 2% × 9
= $5350 ×2/100 × 9
= 5350 × 2 × 9/100
= 10700 × 9/100
= 96300/100
= $963
Thus, Simple Interest = $963
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 = $5350 + $963
= $6313
Thus, Amount to be paid = $6313 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 = $5350
Rate of Simple Interest (SI) or (R) = 2%
And, Time (t) = 9 years
Thus, Amount (A)
= $5350 + ($5350 × 2% × 9)
= $5350 + ($5350 ×2/100 × 9)
= $5350 + (5350 × 2 × 9/100)
= $5350 + (10700 × 9/100)
= $5350 + (96300/100)
= $5350 + $963 = $6313
Thus, Amount (A) to be paid = $6313 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 $5350, the simple interest in 1 year
= 2/100 × 5350
= 2 × 5350/100
= 10700/100 = $107
Thus, simple interest for 1 year = $107
Therefore, simple interest for 9 years
= Simple interest for 1 year × 9
= $107 × 9 = $963
Thus, Simple Interest (SI) = $963
Calculation of Amount
Amount = Principal + Interest
Thus, Amount = $5350 + $963
= $6313
Thus, Amount to be paid = $6313 Answer
Similar Questions
(1) In how much time a principal of $3100 will amount to $3720 at a simple interest of 4% per annum?
(2) Calculate the amount due after 9 years if Christopher borrowed a sum of $6000 at a rate of 2% simple interest.
(3) Calculate the amount due after 9 years if Charles borrowed a sum of $5900 at a rate of 9% simple interest.
(4) Susan had to pay $4197.5 in order to furnish the loan taken 3 years before. If the rate of simple interest was 5% then find the sum borrowed.
(5) What amount will be due after 2 years if Mark borrowed a sum of $3700 at a 6% simple interest?
(6) Calculate the amount due after 9 years if Susan borrowed a sum of $5650 at a rate of 9% simple interest.
(7) Calculate the amount due after 10 years if Susan borrowed a sum of $5650 at a rate of 10% simple interest.
(8) What amount does Susan have to pay after 5 years if he takes a loan of $3650 at 5% simple interest?
(9) Calculate the amount due after 9 years if Susan borrowed a sum of $5650 at a rate of 4% simple interest.
(10) Calculate the amount due after 9 years if David borrowed a sum of $5400 at a rate of 9% simple interest.