Question:
What amount does Barbara have to pay after 6 years if he takes a loan of $3550 at 10% simple interest?
Correct Answer
$5680
Solution And Explanation
Solution
Given,
Principal (P) = $3550
Rate of Simple Interest (SI) = 10%
Time (t) = 6 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) = $3550 × 10% × 6
= $3550 ×10/100 × 6
= 3550 × 10 × 6/100
= 35500 × 6/100
= 213000/100
= $2130
Thus, Simple Interest = $2130
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 = $3550 + $2130
= $5680
Thus, Amount to be paid = $5680 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 = $3550
Rate of Simple Interest (SI) or (R) = 10%
And, Time (t) = 6 years
Thus, Amount (A)
= $3550 + ($3550 × 10% × 6)
= $3550 + ($3550 ×10/100 × 6)
= $3550 + (3550 × 10 × 6/100)
= $3550 + (35500 × 6/100)
= $3550 + (213000/100)
= $3550 + $2130 = $5680
Thus, Amount (A) to be paid = $5680 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 $3550, the simple interest in 1 year
= 10/100 × 3550
= 10 × 3550/100
= 35500/100 = $355
Thus, simple interest for 1 year = $355
Therefore, simple interest for 6 years
= Simple interest for 1 year × 6
= $355 × 6 = $2130
Thus, Simple Interest (SI) = $2130
Calculation of Amount
Amount = Principal + Interest
Thus, Amount = $3550 + $2130
= $5680
Thus, Amount to be paid = $5680 Answer
Similar Questions
(1) Calculate the amount due after 10 years if William borrowed a sum of $5500 at a rate of 5% simple interest.
(2) Thomas had to pay $4256 in order to furnish the loan taken 3 years before. If the rate of simple interest was 4% then find the sum borrowed.
(3) How much loan did Linda borrow 5 years ago at a rate of simple interest 3% per annum, if he paid $6152.5 to clear it?
(4) Calculate the amount due after 9 years if Robert borrowed a sum of $5100 at a rate of 5% simple interest.
(5) Calculate the amount due if Jessica borrowed a sum of $3750 at 5% simple interest for 4 years.
(6) What amount does Robert have to pay after 6 years if he takes a loan of $3100 at 5% simple interest?
(7) Calculate the amount due after 9 years if Linda borrowed a sum of $5350 at a rate of 9% simple interest.
(8) What amount does Susan have to pay after 5 years if he takes a loan of $3650 at 9% simple interest?
(9) Matthew took a loan of $6400 at the rate of 7% simple interest per annum. If he paid an amount of $10432 to clear the loan, then find the time period of the loan.
(10) Calculate the amount due after 10 years if Barbara borrowed a sum of $5550 at a rate of 6% simple interest.