Question:
Calculate the amount due if Joseph borrowed a sum of $3700 at 3% simple interest for 4 years.
Correct Answer
$4144
Solution And Explanation
Solution
Given,
Principal (P) = $3700
Rate of Simple Interest (SI) = 3%
Time (t) = 4 years
Thus, Amount (A) = ?
The Rate of Interest is always calculated per annum, i.e. per year.
Thus, here 3% simple interest means, Rate of Simple Interest (SI) is 3% 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 × 3% × 4
= $3700 ×3/100 × 4
= 3700 × 3 × 4/100
= 11100 × 4/100
= 44400/100
= $444
Thus, Simple Interest = $444
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 + $444
= $4144
Thus, Amount to be paid = $4144 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) = 3%
And, Time (t) = 4 years
Thus, Amount (A)
= $3700 + ($3700 × 3% × 4)
= $3700 + ($3700 ×3/100 × 4)
= $3700 + (3700 × 3 × 4/100)
= $3700 + (11100 × 4/100)
= $3700 + (44400/100)
= $3700 + $444 = $4144
Thus, Amount (A) to be paid = $4144 Answer
Method (3) Unitary Method
Calculation of Amount using Unitary Method
Calculation of Interest using Unitary Method
Here, given Rate of Simple Interest = 3%
This, means, $3 per $100 per year
∵ For $100, the simple interest for 1 year = $3
∴ For $1, the simple interest for 1 year = 3/100
∴ For $3700, the simple interest in 1 year
= 3/100 × 3700
= 3 × 3700/100
= 11100/100 = $111
Thus, simple interest for 1 year = $111
Therefore, simple interest for 4 years
= Simple interest for 1 year × 4
= $111 × 4 = $444
Thus, Simple Interest (SI) = $444
Calculation of Amount
Amount = Principal + Interest
Thus, Amount = $3700 + $444
= $4144
Thus, Amount to be paid = $4144 Answer
Similar Questions
(1) Sandra took a loan of $6900 at the rate of 6% simple interest per annum. If he paid an amount of $11040 to clear the loan, then find the time period of the loan.
(2) Sandra took a loan of $6900 at the rate of 7% simple interest per annum. If he paid an amount of $10764 to clear the loan, then find the time period of the loan.
(3) What amount does Barbara have to pay after 6 years if he takes a loan of $3550 at 7% simple interest?
(4) Calculate the amount due if Barbara borrowed a sum of $3550 at 2% simple interest for 3 years.
(5) What amount will be due after 2 years if Christopher borrowed a sum of $3500 at a 7% simple interest?
(6) What amount does Mary have to pay after 6 years if he takes a loan of $3050 at 2% simple interest?
(7) If Kenneth paid $6000 to settle his loan which he had taken 4 years before at a simple interest of 5%, then find the loan taken.
(8) Calculate the amount due if Karen borrowed a sum of $3950 at 8% simple interest for 3 years.
(9) In how much time a principal of $3150 will amount to $3654 at a simple interest of 4% per annum?
(10) Jennifer took a loan of $4500 at the rate of 10% simple interest per annum. If he paid an amount of $7650 to clear the loan, then find the time period of the loan.