Question:
What amount will be due after 2 years if Matthew borrowed a sum of $3600 at a 9% simple interest?
Correct Answer
$4248
Solution And Explanation
Solution
Given,
Principal (P) = $3600
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) = $3600 × 9% × 2
= $3600 ×9/100 × 2
= 3600 × 9 × 2/100
= 32400 × 2/100
= 64800/100
= $648
Thus, Simple Interest = $648
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 = $3600 + $648
= $4248
Thus, Amount to be paid = $4248 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 = $3600
Rate of Simple Interest (SI) or (R) = 9%
And, Time (t) = 2 years
Thus, Amount (A)
= $3600 + ($3600 × 9% × 2)
= $3600 + ($3600 ×9/100 × 2)
= $3600 + (3600 × 9 × 2/100)
= $3600 + (32400 × 2/100)
= $3600 + (64800/100)
= $3600 + $648 = $4248
Thus, Amount (A) to be paid = $4248 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 $3600, the simple interest in 1 year
= 9/100 × 3600
= 9 × 3600/100
= 32400/100 = $324
Thus, simple interest for 1 year = $324
Therefore, simple interest for 2 years
= Simple interest for 1 year × 2
= $324 × 2 = $648
Thus, Simple Interest (SI) = $648
Calculation of Amount
Amount = Principal + Interest
Thus, Amount = $3600 + $648
= $4248
Thus, Amount to be paid = $4248 Answer
Similar Questions
(1) What amount does William have to pay after 5 years if he takes a loan of $3500 at 5% simple interest?
(2) Anthony took a loan of $6600 at the rate of 9% simple interest per annum. If he paid an amount of $11352 to clear the loan, then find the time period of the loan.
(3) Find the amount to be paid if Richard borrowed a sum of $5600 at 3% simple interest for 7 years.
(4) Calculate the amount due if Richard borrowed a sum of $3600 at 10% simple interest for 4 years.
(5) Mark took a loan of $6800 at the rate of 10% simple interest per annum. If he paid an amount of $13600 to clear the loan, then find the time period of the loan.
(6) Margaret took a loan of $6700 at the rate of 6% simple interest per annum. If he paid an amount of $10318 to clear the loan, then find the time period of the loan.
(7) Find the amount to be paid if David borrowed a sum of $5400 at 9% simple interest for 8 years.
(8) Joseph took a loan of $5400 at the rate of 10% simple interest per annum. If he paid an amount of $10800 to clear the loan, then find the time period of the loan.
(9) What amount will be due after 2 years if William borrowed a sum of $3250 at a 7% simple interest?
(10) Linda took a loan of $4700 at the rate of 8% simple interest per annum. If he paid an amount of $6956 to clear the loan, then find the time period of the loan.