Question:
Find the amount to be paid if Susan borrowed a sum of $5650 at 10% simple interest for 7 years.
Correct Answer
$9605
Solution And Explanation
Solution
Given,
Principal (P) = $5650
Rate of Simple Interest (SI) = 10%
Time (t) = 7 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) = $5650 × 10% × 7
= $5650 ×10/100 × 7
= 5650 × 10 × 7/100
= 56500 × 7/100
= 395500/100
= $3955
Thus, Simple Interest = $3955
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 + $3955
= $9605
Thus, Amount to be paid = $9605 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) = 10%
And, Time (t) = 7 years
Thus, Amount (A)
= $5650 + ($5650 × 10% × 7)
= $5650 + ($5650 ×10/100 × 7)
= $5650 + (5650 × 10 × 7/100)
= $5650 + (56500 × 7/100)
= $5650 + (395500/100)
= $5650 + $3955 = $9605
Thus, Amount (A) to be paid = $9605 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 $5650, the simple interest in 1 year
= 10/100 × 5650
= 10 × 5650/100
= 56500/100 = $565
Thus, simple interest for 1 year = $565
Therefore, simple interest for 7 years
= Simple interest for 1 year × 7
= $565 × 7 = $3955
Thus, Simple Interest (SI) = $3955
Calculation of Amount
Amount = Principal + Interest
Thus, Amount = $5650 + $3955
= $9605
Thus, Amount to be paid = $9605 Answer
Similar Questions
(1) If Charles borrowed $3900 from a bank at a rate of 3% simple interest per annum then find the amount to be paid after 2 years.
(2) Susan had to pay $3978.5 in order to furnish the loan taken 3 years before. If the rate of simple interest was 3% then find the sum borrowed.
(3) Lisa took a loan of $6100 at the rate of 10% simple interest per annum. If he paid an amount of $11590 to clear the loan, then find the time period of the loan.
(4) Calculate the amount due if Barbara borrowed a sum of $3550 at 9% simple interest for 3 years.
(5) What amount does John have to pay after 5 years if he takes a loan of $3200 at 8% simple interest?
(6) What amount does Susan have to pay after 5 years if he takes a loan of $3650 at 6% simple interest?
(7) Jennifer took a loan of $4500 at the rate of 6% simple interest per annum. If he paid an amount of $6660 to clear the loan, then find the time period of the loan.
(8) Robert had to pay $3286 in order to furnish the loan taken 3 years before. If the rate of simple interest was 2% then find the sum borrowed.
(9) Calculate the amount due after 10 years if Richard borrowed a sum of $5600 at a rate of 4% simple interest.
(10) Find the amount to be paid if Patricia borrowed a sum of $5150 at 5% simple interest for 8 years.