Question:
Calculate the amount due after 10 years if Barbara borrowed a sum of $5550 at a rate of 10% simple interest.
Correct Answer
$11100
Solution And Explanation
Solution
Given,
Principal (P) = $5550
Rate of Simple Interest (SI) = 10%
Time (t) = 10 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) = $5550 × 10% × 10
= $5550 ×10/100 × 10
= 5550 × 10 × 10/100
= 55500 × 10/100
= 555000/100
= $5550
Thus, Simple Interest = $5550
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 = $5550 + $5550
= $11100
Thus, Amount to be paid = $11100 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 = $5550
Rate of Simple Interest (SI) or (R) = 10%
And, Time (t) = 10 years
Thus, Amount (A)
= $5550 + ($5550 × 10% × 10)
= $5550 + ($5550 ×10/100 × 10)
= $5550 + (5550 × 10 × 10/100)
= $5550 + (55500 × 10/100)
= $5550 + (555000/100)
= $5550 + $5550 = $11100
Thus, Amount (A) to be paid = $11100 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 $5550, the simple interest in 1 year
= 10/100 × 5550
= 10 × 5550/100
= 55500/100 = $555
Thus, simple interest for 1 year = $555
Therefore, simple interest for 10 years
= Simple interest for 1 year × 10
= $555 × 10 = $5550
Thus, Simple Interest (SI) = $5550
Calculation of Amount
Amount = Principal + Interest
Thus, Amount = $5550 + $5550
= $11100
Thus, Amount to be paid = $11100 Answer
Similar Questions
(1) Calculate the amount due if Sarah borrowed a sum of $3850 at 9% simple interest for 3 years.
(2) What amount does Patricia have to pay after 6 years if he takes a loan of $3150 at 3% simple interest?
(3) What amount does Karen have to pay after 6 years if he takes a loan of $3950 at 8% simple interest?
(4) If Michael paid $3960 to settle his loan which he had taken 4 years before at a simple interest of 5%, then find the loan taken.
(5) David took a loan of $4800 at the rate of 9% simple interest per annum. If he paid an amount of $9120 to clear the loan, then find the time period of the loan.
(6) Jessica took a loan of $5500 at the rate of 8% simple interest per annum. If he paid an amount of $9900 to clear the loan, then find the time period of the loan.
(7) Joseph took a loan of $5400 at the rate of 10% simple interest per annum. If he paid an amount of $9720 to clear the loan, then find the time period of the loan.
(8) What amount does Barbara have to pay after 6 years if he takes a loan of $3550 at 3% simple interest?
(9) Margaret took a loan of $6700 at the rate of 7% simple interest per annum. If he paid an amount of $9514 to clear the loan, then find the time period of the loan.
(10) In how much time a principal of $3150 will amount to $3780 at a simple interest of 4% per annum?