Question:
What amount will be due after 2 years if Thomas borrowed a sum of $3400 at a 9% simple interest?
Correct Answer
$4012
Solution And Explanation
Solution
Given,
Principal (P) = $3400
Rate of Simple Interest (SI) = 9%
Time (t) = 2 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) = $3400 × 9% × 2
= $3400 ×9/100 × 2
= 3400 × 9 × 2/100
= 30600 × 2/100
= 61200/100
= $612
Thus, Simple Interest = $612
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 = $3400 + $612
= $4012
Thus, Amount to be paid = $4012 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 = $3400
Rate of Simple Interest (SI) or (R) = 9%
And, Time (t) = 2 years
Thus, Amount (A)
= $3400 + ($3400 × 9% × 2)
= $3400 + ($3400 ×9/100 × 2)
= $3400 + (3400 × 9 × 2/100)
= $3400 + (30600 × 2/100)
= $3400 + (61200/100)
= $3400 + $612 = $4012
Thus, Amount (A) to be paid = $4012 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 $3400, the simple interest in 1 year
= 9/100 × 3400
= 9 × 3400/100
= 30600/100 = $306
Thus, simple interest for 1 year = $306
Therefore, simple interest for 2 years
= Simple interest for 1 year × 2
= $306 × 2 = $612
Thus, Simple Interest (SI) = $612
Calculation of Amount
Amount = Principal + Interest
Thus, Amount = $3400 + $612
= $4012
Thus, Amount to be paid = $4012 Answer
Similar Questions
(1) Calculate the amount due after 9 years if John borrowed a sum of $5200 at a rate of 6% simple interest.
(2) Calculate the amount due if Elizabeth borrowed a sum of $3450 at 2% simple interest for 3 years.
(3) Find the amount to be paid if Richard borrowed a sum of $5600 at 3% simple interest for 8 years.
(4) Daniel took a loan of $6200 at the rate of 6% simple interest per annum. If he paid an amount of $8804 to clear the loan, then find the time period of the loan.
(5) Calculate the amount due if John borrowed a sum of $3200 at 9% simple interest for 4 years.
(6) Matthew took a loan of $6400 at the rate of 8% simple interest per annum. If he paid an amount of $9984 to clear the loan, then find the time period of the loan.
(7) Sandra took a loan of $6900 at the rate of 7% simple interest per annum. If he paid an amount of $10281 to clear the loan, then find the time period of the loan.
(8) Calculate the amount due if Mary borrowed a sum of $3050 at 4% simple interest for 4 years.
(9) Find the amount to be paid if Barbara borrowed a sum of $5550 at 2% simple interest for 8 years.
(10) Find the amount to be paid if Jennifer borrowed a sum of $5250 at 3% simple interest for 7 years.