Question:
Calculate the amount due if Joseph borrowed a sum of $3700 at 5% simple interest for 3 years.
Correct Answer
$4255
Solution And Explanation
Solution
Given,
Principal (P) = $3700
Rate of Simple Interest (SI) = 5%
Time (t) = 3 years
Thus, Amount (A) = ?
The Rate of Interest is always calculated per annum, i.e. per year.
Thus, here 5% simple interest means, Rate of Simple Interest (SI) is 5% 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) = $3700 × 5% × 3
= $3700 ×5/100 × 3
= 3700 × 5 × 3/100
= 18500 × 3/100
= 55500/100
= $555
Thus, Simple Interest = $555
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 = $3700 + $555
= $4255
Thus, Amount to be paid = $4255 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 = $3700
Rate of Simple Interest (SI) or (R) = 5%
And, Time (t) = 3 years
Thus, Amount (A)
= $3700 + ($3700 × 5% × 3)
= $3700 + ($3700 ×5/100 × 3)
= $3700 + (3700 × 5 × 3/100)
= $3700 + (18500 × 3/100)
= $3700 + (55500/100)
= $3700 + $555 = $4255
Thus, Amount (A) to be paid = $4255 Answer
Method (3) Unitary Method
Calculation of Amount using Unitary Method
Calculation of Interest using Unitary Method
Here, given Rate of Simple Interest = 5%
This, means, $5 per $100 per year
∵ For $100, the simple interest for 1 year = $5
∴ For $1, the simple interest for 1 year = 5/100
∴ For $3700, the simple interest in 1 year
= 5/100 × 3700
= 5 × 3700/100
= 18500/100 = $185
Thus, simple interest for 1 year = $185
Therefore, simple interest for 3 years
= Simple interest for 1 year × 3
= $185 × 3 = $555
Thus, Simple Interest (SI) = $555
Calculation of Amount
Amount = Principal + Interest
Thus, Amount = $3700 + $555
= $4255
Thus, Amount to be paid = $4255 Answer
Similar Questions
(1) Calculate the amount due after 9 years if William borrowed a sum of $5500 at a rate of 2% simple interest.
(2) What amount does Karen have to pay after 5 years if he takes a loan of $3950 at 4% simple interest?
(3) Calculate the amount due after 10 years if Barbara borrowed a sum of $5550 at a rate of 8% simple interest.
(4) Sarah took a loan of $5700 at the rate of 6% simple interest per annum. If he paid an amount of $8094 to clear the loan, then find the time period of the loan.
(5) In how much time a principal of $3000 will amount to $3240 at a simple interest of 2% per annum?
(6) Find the amount to be paid if Robert borrowed a sum of $5100 at 5% simple interest for 7 years.
(7) Calculate the amount due if Jessica borrowed a sum of $3750 at 2% simple interest for 4 years.
(8) How much loan did Jason borrow 5 years ago at a rate of simple interest 4% per annum, if he paid $9240 to clear it?
(9) Calculate the amount due after 9 years if Charles borrowed a sum of $5900 at a rate of 8% simple interest.
(10) Karen took a loan of $5900 at the rate of 8% simple interest per annum. If he paid an amount of $10148 to clear the loan, then find the time period of the loan.