Question:
Find the amount to be paid if Christopher borrowed a sum of $6000 at 10% simple interest for 8 years.
Correct Answer
$10800
Solution And Explanation
Solution
Given,
Principal (P) = $6000
Rate of Simple Interest (SI) = 10%
Time (t) = 8 years
Thus, Amount (A) = ?
The Rate of Interest is always calculated per annum, i.e. per year.
Thus, here 10% simple interest means, Rate of Simple Interest (SI) is 10% 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 × 10% × 8
= $6000 ×10/100 × 8
= 6000 × 10 × 8/100
= 60000 × 8/100
= 480000/100
= $4800
Thus, Simple Interest = $4800
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 + $4800
= $10800
Thus, Amount to be paid = $10800 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) = 10%
And, Time (t) = 8 years
Thus, Amount (A)
= $6000 + ($6000 × 10% × 8)
= $6000 + ($6000 ×10/100 × 8)
= $6000 + (6000 × 10 × 8/100)
= $6000 + (60000 × 8/100)
= $6000 + (480000/100)
= $6000 + $4800 = $10800
Thus, Amount (A) to be paid = $10800 Answer
Method (3) Unitary Method
Calculation of Amount using Unitary Method
Calculation of Interest using Unitary Method
Here, given Rate of Simple Interest = 10%
This, means, $10 per $100 per year
∵ For $100, the simple interest for 1 year = $10
∴ For $1, the simple interest for 1 year = 10/100
∴ For $6000, the simple interest in 1 year
= 10/100 × 6000
= 10 × 6000/100
= 60000/100 = $600
Thus, simple interest for 1 year = $600
Therefore, simple interest for 8 years
= Simple interest for 1 year × 8
= $600 × 8 = $4800
Thus, Simple Interest (SI) = $4800
Calculation of Amount
Amount = Principal + Interest
Thus, Amount = $6000 + $4800
= $10800
Thus, Amount to be paid = $10800 Answer
Similar Questions
(1) Find the amount to be paid if Mary borrowed a sum of $5050 at 6% simple interest for 7 years.
(2) Richard took a loan of $5200 at the rate of 9% simple interest per annum. If he paid an amount of $8476 to clear the loan, then find the time period of the loan.
(3) Calculate the amount due if Joseph borrowed a sum of $3700 at 3% simple interest for 4 years.
(4) Calculate the amount due after 9 years if Mary borrowed a sum of $5050 at a rate of 10% simple interest.
(5) What amount does John have to pay after 5 years if he takes a loan of $3200 at 8% simple interest?
(6) Find the amount to be paid if David borrowed a sum of $5400 at 6% simple interest for 7 years.
(7) What amount does Richard have to pay after 5 years if he takes a loan of $3600 at 9% simple interest?
(8) Calculate the amount due if William borrowed a sum of $3500 at 6% simple interest for 4 years.
(9) What amount will be due after 2 years if Joseph borrowed a sum of $3350 at a 9% simple interest?
(10) If Kimberly paid $5208 to settle his loan which he had taken 4 years before at a simple interest of 3%, then find the loan taken.