Question:
Calculate the amount due if Linda borrowed a sum of $3350 at 3% simple interest for 3 years.
Correct Answer
$3651.5
Solution And Explanation
Solution
Given,
Principal (P) = $3350
Rate of Simple Interest (SI) = 3%
Time (t) = 3 years
Thus, Amount (A) = ?
The Rate of Interest is always calculated per annum, i.e. per year.
Thus, here 3% simple interest means, Rate of Simple Interest (SI) is 3% 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 × 3% × 3
= $3350 ×3/100 × 3
= 3350 × 3 × 3/100
= 10050 × 3/100
= 30150/100
= $301.5
Thus, Simple Interest = $301.5
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 + $301.5
= $3651.5
Thus, Amount to be paid = $3651.5 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) = 3%
And, Time (t) = 3 years
Thus, Amount (A)
= $3350 + ($3350 × 3% × 3)
= $3350 + ($3350 ×3/100 × 3)
= $3350 + (3350 × 3 × 3/100)
= $3350 + (10050 × 3/100)
= $3350 + (30150/100)
= $3350 + $301.5 = $3651.5
Thus, Amount (A) to be paid = $3651.5 Answer
Method (3) Unitary Method
Calculation of Amount using Unitary Method
Calculation of Interest using Unitary Method
Here, given Rate of Simple Interest = 3%
This, means, $3 per $100 per year
∵ For $100, the simple interest for 1 year = $3
∴ For $1, the simple interest for 1 year = 3/100
∴ For $3350, the simple interest in 1 year
= 3/100 × 3350
= 3 × 3350/100
= 10050/100 = $100.5
Thus, simple interest for 1 year = $100.5
Therefore, simple interest for 3 years
= Simple interest for 1 year × 3
= $100.5 × 3 = $301.5
Thus, Simple Interest (SI) = $301.5
Calculation of Amount
Amount = Principal + Interest
Thus, Amount = $3350 + $301.5
= $3651.5
Thus, Amount to be paid = $3651.5 Answer
Similar Questions
(1) Find the amount to be paid if Charles borrowed a sum of $5900 at 4% simple interest for 8 years.
(2) Find the amount to be paid if Susan borrowed a sum of $5650 at 10% simple interest for 7 years.
(3) How much loan did Amanda borrow 5 years ago at a rate of simple interest 4% per annum, if he paid $8580 to clear it?
(4) In how much time a principal of $3000 will amount to $3180 at a simple interest of 3% per annum?
(5) Find the amount to be paid if Patricia borrowed a sum of $5150 at 6% simple interest for 7 years.
(6) What amount does Jennifer have to pay after 5 years if he takes a loan of $3250 at 3% simple interest?
(7) Calculate the amount due after 10 years if Robert borrowed a sum of $5100 at a rate of 7% simple interest.
(8) Calculate the amount due after 10 years if Sarah borrowed a sum of $5850 at a rate of 3% simple interest.
(9) What amount will be due after 2 years if Kenneth borrowed a sum of $4000 at a 5% simple interest?
(10) What amount does Joseph have to pay after 5 years if he takes a loan of $3700 at 8% simple interest?