Question:
What amount will be due after 2 years if Richard borrowed a sum of $3300 at a 10% simple interest?
Correct Answer
$3960
Solution And Explanation
Solution
Given,
Principal (P) = $3300
Rate of Simple Interest (SI) = 10%
Time (t) = 2 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) = $3300 × 10% × 2
= $3300 ×10/100 × 2
= 3300 × 10 × 2/100
= 33000 × 2/100
= 66000/100
= $660
Thus, Simple Interest = $660
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 = $3300 + $660
= $3960
Thus, Amount to be paid = $3960 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 = $3300
Rate of Simple Interest (SI) or (R) = 10%
And, Time (t) = 2 years
Thus, Amount (A)
= $3300 + ($3300 × 10% × 2)
= $3300 + ($3300 ×10/100 × 2)
= $3300 + (3300 × 10 × 2/100)
= $3300 + (33000 × 2/100)
= $3300 + (66000/100)
= $3300 + $660 = $3960
Thus, Amount (A) to be paid = $3960 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 $3300, the simple interest in 1 year
= 10/100 × 3300
= 10 × 3300/100
= 33000/100 = $330
Thus, simple interest for 1 year = $330
Therefore, simple interest for 2 years
= Simple interest for 1 year × 2
= $330 × 2 = $660
Thus, Simple Interest (SI) = $660
Calculation of Amount
Amount = Principal + Interest
Thus, Amount = $3300 + $660
= $3960
Thus, Amount to be paid = $3960 Answer
Similar Questions
(1) Find the amount to be paid if David borrowed a sum of $5400 at 8% simple interest for 7 years.
(2) Calculate the amount due if Charles borrowed a sum of $3900 at 8% simple interest for 4 years.
(3) Betty took a loan of $6500 at the rate of 7% simple interest per annum. If he paid an amount of $9230 to clear the loan, then find the time period of the loan.
(4) Find the amount to be paid if Mary borrowed a sum of $5050 at 9% simple interest for 8 years.
(5) How much loan did Jeffrey borrow 5 years ago at a rate of simple interest 5% per annum, if he paid $9750 to clear it?
(6) Calculate the amount due if William borrowed a sum of $3500 at 3% simple interest for 4 years.
(7) Find the amount to be paid if Jessica borrowed a sum of $5750 at 2% simple interest for 7 years.
(8) Calculate the amount due after 10 years if Jessica borrowed a sum of $5750 at a rate of 2% simple interest.
(9) What amount does Jessica have to pay after 5 years if he takes a loan of $3750 at 2% simple interest?
(10) If Steven paid $5520 to settle his loan which he had taken 4 years before at a simple interest of 5%, then find the loan taken.