Question:
Find the amount to be paid if Christopher borrowed a sum of $6000 at 6% simple interest for 7 years.
Correct Answer
$8520
Solution And Explanation
Solution
Given,
Principal (P) = $6000
Rate of Simple Interest (SI) = 6%
Time (t) = 7 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) = $6000 × 6% × 7
= $6000 ×6/100 × 7
= 6000 × 6 × 7/100
= 36000 × 7/100
= 252000/100
= $2520
Thus, Simple Interest = $2520
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 + $2520
= $8520
Thus, Amount to be paid = $8520 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) = 6%
And, Time (t) = 7 years
Thus, Amount (A)
= $6000 + ($6000 × 6% × 7)
= $6000 + ($6000 ×6/100 × 7)
= $6000 + (6000 × 6 × 7/100)
= $6000 + (36000 × 7/100)
= $6000 + (252000/100)
= $6000 + $2520 = $8520
Thus, Amount (A) to be paid = $8520 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 $6000, the simple interest in 1 year
= 6/100 × 6000
= 6 × 6000/100
= 36000/100 = $360
Thus, simple interest for 1 year = $360
Therefore, simple interest for 7 years
= Simple interest for 1 year × 7
= $360 × 7 = $2520
Thus, Simple Interest (SI) = $2520
Calculation of Amount
Amount = Principal + Interest
Thus, Amount = $6000 + $2520
= $8520
Thus, Amount to be paid = $8520 Answer
Similar Questions
(1) Find the amount to be paid if Christopher borrowed a sum of $6000 at 10% simple interest for 8 years.
(2) What amount does Sarah have to pay after 5 years if he takes a loan of $3850 at 4% simple interest?
(3) Find the amount to be paid if Susan borrowed a sum of $5650 at 9% simple interest for 8 years.
(4) Calculate the amount due if Jennifer borrowed a sum of $3250 at 3% simple interest for 3 years.
(5) Margaret took a loan of $6700 at the rate of 9% simple interest per annum. If he paid an amount of $10921 to clear the loan, then find the time period of the loan.
(6) Calculate the amount due after 10 years if Joseph borrowed a sum of $5700 at a rate of 8% simple interest.
(7) Lisa took a loan of $6100 at the rate of 8% simple interest per annum. If he paid an amount of $9516 to clear the loan, then find the time period of the loan.
(8) 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.
(9) What amount does Michael have to pay after 5 years if he takes a loan of $3300 at 8% simple interest?
(10) What amount does Elizabeth have to pay after 6 years if he takes a loan of $3450 at 6% simple interest?