Question:
Find the amount to be paid if Christopher borrowed a sum of $6000 at 4% simple interest for 8 years.
Correct Answer
$7920
Solution And Explanation
Solution
Given,
Principal (P) = $6000
Rate of Simple Interest (SI) = 4%
Time (t) = 8 years
Thus, Amount (A) = ?
The Rate of Interest is always calculated per annum, i.e. per year.
Thus, here 4% simple interest means, Rate of Simple Interest (SI) is 4% 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) = $6000 × 4% × 8
= $6000 ×4/100 × 8
= 6000 × 4 × 8/100
= 24000 × 8/100
= 192000/100
= $1920
Thus, Simple Interest = $1920
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 = $6000 + $1920
= $7920
Thus, Amount to be paid = $7920 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 = $6000
Rate of Simple Interest (SI) or (R) = 4%
And, Time (t) = 8 years
Thus, Amount (A)
= $6000 + ($6000 × 4% × 8)
= $6000 + ($6000 ×4/100 × 8)
= $6000 + (6000 × 4 × 8/100)
= $6000 + (24000 × 8/100)
= $6000 + (192000/100)
= $6000 + $1920 = $7920
Thus, Amount (A) to be paid = $7920 Answer
Method (3) Unitary Method
Calculation of Amount using Unitary Method
Calculation of Interest using Unitary Method
Here, given Rate of Simple Interest = 4%
This, means, $4 per $100 per year
∵ For $100, the simple interest for 1 year = $4
∴ For $1, the simple interest for 1 year = 4/100
∴ For $6000, the simple interest in 1 year
= 4/100 × 6000
= 4 × 6000/100
= 24000/100 = $240
Thus, simple interest for 1 year = $240
Therefore, simple interest for 8 years
= Simple interest for 1 year × 8
= $240 × 8 = $1920
Thus, Simple Interest (SI) = $1920
Calculation of Amount
Amount = Principal + Interest
Thus, Amount = $6000 + $1920
= $7920
Thus, Amount to be paid = $7920 Answer
Similar Questions
(1) Donna had to pay $5432 in order to furnish the loan taken 3 years before. If the rate of simple interest was 4% then find the sum borrowed.
(2) Barbara took a loan of $5100 at the rate of 6% simple interest per annum. If he paid an amount of $7242 to clear the loan, then find the time period of the loan.
(3) Daniel took a loan of $6200 at the rate of 8% simple interest per annum. If he paid an amount of $10168 to clear the loan, then find the time period of the loan.
(4) Jennifer had to pay $3542.5 in order to furnish the loan taken 3 years before. If the rate of simple interest was 3% then find the sum borrowed.
(5) If Paul paid $5640 to settle his loan which he had taken 4 years before at a simple interest of 5%, then find the loan taken.
(6) What amount will be due after 2 years if Andrew borrowed a sum of $3900 at a 7% simple interest?
(7) What amount will be due after 2 years if Mark borrowed a sum of $3700 at a 7% simple interest?
(8) Calculate the amount due if Susan borrowed a sum of $3650 at 9% simple interest for 4 years.
(9) Calculate the amount due after 10 years if Jennifer borrowed a sum of $5250 at a rate of 4% simple interest.
(10) Calculate the amount due after 10 years if John borrowed a sum of $5200 at a rate of 2% simple interest.