Question:
What amount does Barbara have to pay after 6 years if he takes a loan of $3550 at 6% simple interest?
Correct Answer
$4828
Solution And Explanation
Solution
Given,
Principal (P) = $3550
Rate of Simple Interest (SI) = 6%
Time (t) = 6 years
Thus, Amount (A) = ?
The Rate of Interest is always calculated per annum, i.e. per year.
Thus, here 6% simple interest means, Rate of Simple Interest (SI) is 6% 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) = $3550 × 6% × 6
= $3550 ×6/100 × 6
= 3550 × 6 × 6/100
= 21300 × 6/100
= 127800/100
= $1278
Thus, Simple Interest = $1278
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 = $3550 + $1278
= $4828
Thus, Amount to be paid = $4828 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 = $3550
Rate of Simple Interest (SI) or (R) = 6%
And, Time (t) = 6 years
Thus, Amount (A)
= $3550 + ($3550 × 6% × 6)
= $3550 + ($3550 ×6/100 × 6)
= $3550 + (3550 × 6 × 6/100)
= $3550 + (21300 × 6/100)
= $3550 + (127800/100)
= $3550 + $1278 = $4828
Thus, Amount (A) to be paid = $4828 Answer
Method (3) Unitary Method
Calculation of Amount using Unitary Method
Calculation of Interest using Unitary Method
Here, given Rate of Simple Interest = 6%
This, means, $6 per $100 per year
∵ For $100, the simple interest for 1 year = $6
∴ For $1, the simple interest for 1 year = 6/100
∴ For $3550, the simple interest in 1 year
= 6/100 × 3550
= 6 × 3550/100
= 21300/100 = $213
Thus, simple interest for 1 year = $213
Therefore, simple interest for 6 years
= Simple interest for 1 year × 6
= $213 × 6 = $1278
Thus, Simple Interest (SI) = $1278
Calculation of Amount
Amount = Principal + Interest
Thus, Amount = $3550 + $1278
= $4828
Thus, Amount to be paid = $4828 Answer
Similar Questions
(1) In how much time a principal of $3200 will amount to $3680 at a simple interest of 5% per annum?
(2) Calculate the amount due after 9 years if Elizabeth borrowed a sum of $5450 at a rate of 3% simple interest.
(3) Kimberly had to pay $4929 in order to furnish the loan taken 3 years before. If the rate of simple interest was 2% then find the sum borrowed.
(4) Calculate the amount due if Richard borrowed a sum of $3600 at 7% simple interest for 3 years.
(5) Calculate the amount due if John borrowed a sum of $3200 at 3% simple interest for 4 years.
(6) How much loan did Susan borrow 5 years ago at a rate of simple interest 4% per annum, if he paid $6780 to clear it?
(7) How much loan did Patricia borrow 5 years ago at a rate of simple interest 3% per annum, if he paid $5922.5 to clear it?
(8) Elizabeth had to pay $3760.5 in order to furnish the loan taken 3 years before. If the rate of simple interest was 3% then find the sum borrowed.
(9) Calculate the amount due after 9 years if Barbara borrowed a sum of $5550 at a rate of 6% simple interest.
(10) If Elizabeth paid $4140 to settle his loan which he had taken 4 years before at a simple interest of 5%, then find the loan taken.