Question:
Calculate the amount due after 9 years if Susan borrowed a sum of $5650 at a rate of 6% simple interest.
Correct Answer
$8701
Solution And Explanation
Solution
Given,
Principal (P) = $5650
Rate of Simple Interest (SI) = 6%
Time (t) = 9 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) = $5650 × 6% × 9
= $5650 ×6/100 × 9
= 5650 × 6 × 9/100
= 33900 × 9/100
= 305100/100
= $3051
Thus, Simple Interest = $3051
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 = $5650 + $3051
= $8701
Thus, Amount to be paid = $8701 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 = $5650
Rate of Simple Interest (SI) or (R) = 6%
And, Time (t) = 9 years
Thus, Amount (A)
= $5650 + ($5650 × 6% × 9)
= $5650 + ($5650 ×6/100 × 9)
= $5650 + (5650 × 6 × 9/100)
= $5650 + (33900 × 9/100)
= $5650 + (305100/100)
= $5650 + $3051 = $8701
Thus, Amount (A) to be paid = $8701 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 $5650, the simple interest in 1 year
= 6/100 × 5650
= 6 × 5650/100
= 33900/100 = $339
Thus, simple interest for 1 year = $339
Therefore, simple interest for 9 years
= Simple interest for 1 year × 9
= $339 × 9 = $3051
Thus, Simple Interest (SI) = $3051
Calculation of Amount
Amount = Principal + Interest
Thus, Amount = $5650 + $3051
= $8701
Thus, Amount to be paid = $8701 Answer
Similar Questions
(1) What amount does Elizabeth have to pay after 6 years if he takes a loan of $3450 at 6% simple interest?
(2) Donna had to pay $5141 in order to furnish the loan taken 3 years before. If the rate of simple interest was 2% then find the sum borrowed.
(3) Find the amount to be paid if Elizabeth borrowed a sum of $5450 at 4% simple interest for 7 years.
(4) How much loan did Karen borrow 5 years ago at a rate of simple interest 5% per annum, if he paid $7437.5 to clear it?
(5) What amount will be due after 2 years if Anthony borrowed a sum of $3650 at a 7% simple interest?
(6) Calculate the amount due if Susan borrowed a sum of $3650 at 8% simple interest for 4 years.
(7) What amount does Barbara have to pay after 6 years if he takes a loan of $3550 at 8% simple interest?
(8) Calculate the amount due after 10 years if Barbara borrowed a sum of $5550 at a rate of 8% simple interest.
(9) Kenneth had to pay $5450 in order to furnish the loan taken 3 years before. If the rate of simple interest was 3% then find the sum borrowed.
(10) Calculate the amount due after 10 years if Elizabeth borrowed a sum of $5450 at a rate of 5% simple interest.