Question:
Calculate the amount due if Jessica borrowed a sum of $3750 at 10% simple interest for 4 years.
Correct Answer
$5250
Solution And Explanation
Solution
Given,
Principal (P) = $3750
Rate of Simple Interest (SI) = 10%
Time (t) = 4 years
Thus, Amount (A) = ?
The Rate of Interest is always calculated per annum, i.e. per year.
Thus, here 10% simple interest means, Rate of Simple Interest (SI) is 10% 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) = $3750 × 10% × 4
= $3750 ×10/100 × 4
= 3750 × 10 × 4/100
= 37500 × 4/100
= 150000/100
= $1500
Thus, Simple Interest = $1500
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 = $3750 + $1500
= $5250
Thus, Amount to be paid = $5250 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 = $3750
Rate of Simple Interest (SI) or (R) = 10%
And, Time (t) = 4 years
Thus, Amount (A)
= $3750 + ($3750 × 10% × 4)
= $3750 + ($3750 ×10/100 × 4)
= $3750 + (3750 × 10 × 4/100)
= $3750 + (37500 × 4/100)
= $3750 + (150000/100)
= $3750 + $1500 = $5250
Thus, Amount (A) to be paid = $5250 Answer
Method (3) Unitary Method
Calculation of Amount using Unitary Method
Calculation of Interest using Unitary Method
Here, given Rate of Simple Interest = 10%
This, means, $10 per $100 per year
∵ For $100, the simple interest for 1 year = $10
∴ For $1, the simple interest for 1 year = 10/100
∴ For $3750, the simple interest in 1 year
= 10/100 × 3750
= 10 × 3750/100
= 37500/100 = $375
Thus, simple interest for 1 year = $375
Therefore, simple interest for 4 years
= Simple interest for 1 year × 4
= $375 × 4 = $1500
Thus, Simple Interest (SI) = $1500
Calculation of Amount
Amount = Principal + Interest
Thus, Amount = $3750 + $1500
= $5250
Thus, Amount to be paid = $5250 Answer
Similar Questions
(1) Calculate the amount due after 9 years if Robert borrowed a sum of $5100 at a rate of 6% simple interest.
(2) Barbara took a loan of $5100 at the rate of 9% simple interest per annum. If he paid an amount of $8313 to clear the loan, then find the time period of the loan.
(3) Thomas took a loan of $5600 at the rate of 10% simple interest per annum. If he paid an amount of $9520 to clear the loan, then find the time period of the loan.
(4) If David paid $3672 to settle his loan which he had taken 4 years before at a simple interest of 2%, then find the loan taken.
(5) What amount does Jennifer have to pay after 6 years if he takes a loan of $3250 at 4% simple interest?
(6) Calculate the amount due after 9 years if Susan borrowed a sum of $5650 at a rate of 2% simple interest.
(7) Jennifer took a loan of $4500 at the rate of 9% simple interest per annum. If he paid an amount of $6930 to clear the loan, then find the time period of the loan.
(8) Lisa took a loan of $6100 at the rate of 9% simple interest per annum. If he paid an amount of $11041 to clear the loan, then find the time period of the loan.
(9) What amount will be due after 2 years if Joseph borrowed a sum of $3350 at a 6% simple interest?
(10) How much loan did Margaret borrow 5 years ago at a rate of simple interest 4% per annum, if he paid $7620 to clear it?