Question:
Calculate the amount due if Linda borrowed a sum of $3350 at 10% simple interest for 3 years.
Correct Answer
$4355
Solution And Explanation
Solution
Given,
Principal (P) = $3350
Rate of Simple Interest (SI) = 10%
Time (t) = 3 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) = $3350 × 10% × 3
= $3350 ×10/100 × 3
= 3350 × 10 × 3/100
= 33500 × 3/100
= 100500/100
= $1005
Thus, Simple Interest = $1005
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 = $3350 + $1005
= $4355
Thus, Amount to be paid = $4355 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 = $3350
Rate of Simple Interest (SI) or (R) = 10%
And, Time (t) = 3 years
Thus, Amount (A)
= $3350 + ($3350 × 10% × 3)
= $3350 + ($3350 ×10/100 × 3)
= $3350 + (3350 × 10 × 3/100)
= $3350 + (33500 × 3/100)
= $3350 + (100500/100)
= $3350 + $1005 = $4355
Thus, Amount (A) to be paid = $4355 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 $3350, the simple interest in 1 year
= 10/100 × 3350
= 10 × 3350/100
= 33500/100 = $335
Thus, simple interest for 1 year = $335
Therefore, simple interest for 3 years
= Simple interest for 1 year × 3
= $335 × 3 = $1005
Thus, Simple Interest (SI) = $1005
Calculation of Amount
Amount = Principal + Interest
Thus, Amount = $3350 + $1005
= $4355
Thus, Amount to be paid = $4355 Answer
Similar Questions
(1) Find the amount to be paid if Richard borrowed a sum of $5600 at 10% simple interest for 7 years.
(2) Richard took a loan of $5200 at the rate of 8% simple interest per annum. If he paid an amount of $8528 to clear the loan, then find the time period of the loan.
(3) What amount does Barbara have to pay after 5 years if he takes a loan of $3550 at 3% simple interest?
(4) Find the amount to be paid if John borrowed a sum of $5200 at 8% simple interest for 7 years.
(5) Elizabeth took a loan of $4900 at the rate of 9% simple interest per annum. If he paid an amount of $7987 to clear the loan, then find the time period of the loan.
(6) What amount does Karen have to pay after 6 years if he takes a loan of $3950 at 3% simple interest?
(7) Find the amount to be paid if Thomas borrowed a sum of $5800 at 5% simple interest for 8 years.
(8) Calculate the amount due after 10 years if John borrowed a sum of $5200 at a rate of 9% simple interest.
(9) Karen took a loan of $5900 at the rate of 6% simple interest per annum. If he paid an amount of $8732 to clear the loan, then find the time period of the loan.
(10) How much loan did Rebecca borrow 5 years ago at a rate of simple interest 5% per annum, if he paid $9562.5 to clear it?