Question:
Calculate the amount due if Michael borrowed a sum of $3300 at 7% simple interest for 4 years.
Correct Answer
$4224
Solution And Explanation
Solution
Given,
Principal (P) = $3300
Rate of Simple Interest (SI) = 7%
Time (t) = 4 years
Thus, Amount (A) = ?
The Rate of Interest is always calculated per annum, i.e. per year.
Thus, here 7% simple interest means, Rate of Simple Interest (SI) is 7% 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 × 7% × 4
= $3300 ×7/100 × 4
= 3300 × 7 × 4/100
= 23100 × 4/100
= 92400/100
= $924
Thus, Simple Interest = $924
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 + $924
= $4224
Thus, Amount to be paid = $4224 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) = 7%
And, Time (t) = 4 years
Thus, Amount (A)
= $3300 + ($3300 × 7% × 4)
= $3300 + ($3300 ×7/100 × 4)
= $3300 + (3300 × 7 × 4/100)
= $3300 + (23100 × 4/100)
= $3300 + (92400/100)
= $3300 + $924 = $4224
Thus, Amount (A) to be paid = $4224 Answer
Method (3) Unitary Method
Calculation of Amount using Unitary Method
Calculation of Interest using Unitary Method
Here, given Rate of Simple Interest = 7%
This, means, $7 per $100 per year
∵ For $100, the simple interest for 1 year = $7
∴ For $1, the simple interest for 1 year = 7/100
∴ For $3300, the simple interest in 1 year
= 7/100 × 3300
= 7 × 3300/100
= 23100/100 = $231
Thus, simple interest for 1 year = $231
Therefore, simple interest for 4 years
= Simple interest for 1 year × 4
= $231 × 4 = $924
Thus, Simple Interest (SI) = $924
Calculation of Amount
Amount = Principal + Interest
Thus, Amount = $3300 + $924
= $4224
Thus, Amount to be paid = $4224 Answer
Similar Questions
(1) Calculate the amount due if Robert borrowed a sum of $3100 at 3% simple interest for 4 years.
(2) Calculate the amount due after 9 years if Thomas borrowed a sum of $5800 at a rate of 6% simple interest.
(3) Jennifer took a loan of $4500 at the rate of 6% simple interest per annum. If he paid an amount of $6930 to clear the loan, then find the time period of the loan.
(4) Calculate the amount due if Karen borrowed a sum of $3950 at 8% simple interest for 3 years.
(5) In how much time a principal of $3150 will amount to $3433.5 at a simple interest of 3% per annum?
(6) Find the amount to be paid if William borrowed a sum of $5500 at 10% simple interest for 7 years.
(7) Calculate the amount due after 10 years if Thomas borrowed a sum of $5800 at a rate of 8% simple interest.
(8) What amount will be due after 2 years if Charles borrowed a sum of $3450 at a 8% simple interest?
(9) If Steven paid $5336 to settle his loan which he had taken 4 years before at a simple interest of 4%, then find the loan taken.
(10) Linda took a loan of $4700 at the rate of 8% simple interest per annum. If he paid an amount of $7332 to clear the loan, then find the time period of the loan.