Question:
Find the amount to be paid if James borrowed a sum of $5000 at 9% simple interest for 8 years.
Correct Answer
$8600
Solution And Explanation
Solution
Given,
Principal (P) = $5000
Rate of Simple Interest (SI) = 9%
Time (t) = 8 years
Thus, Amount (A) = ?
The Rate of Interest is always calculated per annum, i.e. per year.
Thus, here 9% simple interest means, Rate of Simple Interest (SI) is 9% 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) = $5000 × 9% × 8
= $5000 ×9/100 × 8
= 5000 × 9 × 8/100
= 45000 × 8/100
= 360000/100
= $3600
Thus, Simple Interest = $3600
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 = $5000 + $3600
= $8600
Thus, Amount to be paid = $8600 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 = $5000
Rate of Simple Interest (SI) or (R) = 9%
And, Time (t) = 8 years
Thus, Amount (A)
= $5000 + ($5000 × 9% × 8)
= $5000 + ($5000 ×9/100 × 8)
= $5000 + (5000 × 9 × 8/100)
= $5000 + (45000 × 8/100)
= $5000 + (360000/100)
= $5000 + $3600 = $8600
Thus, Amount (A) to be paid = $8600 Answer
Method (3) Unitary Method
Calculation of Amount using Unitary Method
Calculation of Interest using Unitary Method
Here, given Rate of Simple Interest = 9%
This, means, $9 per $100 per year
∵ For $100, the simple interest for 1 year = $9
∴ For $1, the simple interest for 1 year = 9/100
∴ For $5000, the simple interest in 1 year
= 9/100 × 5000
= 9 × 5000/100
= 45000/100 = $450
Thus, simple interest for 1 year = $450
Therefore, simple interest for 8 years
= Simple interest for 1 year × 8
= $450 × 8 = $3600
Thus, Simple Interest (SI) = $3600
Calculation of Amount
Amount = Principal + Interest
Thus, Amount = $5000 + $3600
= $8600
Thus, Amount to be paid = $8600 Answer
Similar Questions
(1) Find the amount to be paid if Barbara borrowed a sum of $5550 at 2% simple interest for 7 years.
(2) How much loan did Susan borrow 5 years ago at a rate of simple interest 5% per annum, if he paid $7062.5 to clear it?
(3) Calculate the amount due if William borrowed a sum of $3500 at 5% simple interest for 4 years.
(4) If Jennifer borrowed $3250 from a bank at a rate of 2% simple interest per annum then find the amount to be paid after 2 years.
(5) Find the amount to be paid if Elizabeth borrowed a sum of $5450 at 5% simple interest for 8 years.
(6) Calculate the amount due if Linda borrowed a sum of $3350 at 8% simple interest for 3 years.
(7) What amount will be due after 2 years if John borrowed a sum of $3100 at a 8% simple interest?
(8) Calculate the amount due if Joseph borrowed a sum of $3700 at 9% simple interest for 4 years.
(9) Calculate the amount due after 9 years if Sarah borrowed a sum of $5850 at a rate of 8% simple interest.
(10) Calculate the amount due if Robert borrowed a sum of $3100 at 4% simple interest for 4 years.