Question:
Calculate the amount due if Michael borrowed a sum of $3300 at 9% simple interest for 4 years.
Correct Answer
$4488
Solution And Explanation
Solution
Given,
Principal (P) = $3300
Rate of Simple Interest (SI) = 9%
Time (t) = 4 years
Thus, Amount (A) = ?
The Rate of Interest is always calculated per annum, i.e. per year.
Thus, here 9% simple interest means, Rate of Simple Interest (SI) is 9% 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) = $3300 × 9% × 4
= $3300 ×9/100 × 4
= 3300 × 9 × 4/100
= 29700 × 4/100
= 118800/100
= $1188
Thus, Simple Interest = $1188
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 = $3300 + $1188
= $4488
Thus, Amount to be paid = $4488 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 = $3300
Rate of Simple Interest (SI) or (R) = 9%
And, Time (t) = 4 years
Thus, Amount (A)
= $3300 + ($3300 × 9% × 4)
= $3300 + ($3300 ×9/100 × 4)
= $3300 + (3300 × 9 × 4/100)
= $3300 + (29700 × 4/100)
= $3300 + (118800/100)
= $3300 + $1188 = $4488
Thus, Amount (A) to be paid = $4488 Answer
Method (3) Unitary Method
Calculation of Amount using Unitary Method
Calculation of Interest using Unitary Method
Here, given Rate of Simple Interest = 9%
This, means, $9 per $100 per year
∵ For $100, the simple interest for 1 year = $9
∴ For $1, the simple interest for 1 year = 9/100
∴ For $3300, the simple interest in 1 year
= 9/100 × 3300
= 9 × 3300/100
= 29700/100 = $297
Thus, simple interest for 1 year = $297
Therefore, simple interest for 4 years
= Simple interest for 1 year × 4
= $297 × 4 = $1188
Thus, Simple Interest (SI) = $1188
Calculation of Amount
Amount = Principal + Interest
Thus, Amount = $3300 + $1188
= $4488
Thus, Amount to be paid = $4488 Answer
Similar Questions
(1) What amount does Michael have to pay after 5 years if he takes a loan of $3300 at 5% simple interest?
(2) What amount does Mary have to pay after 5 years if he takes a loan of $3050 at 4% simple interest?
(3) Michael took a loan of $4600 at the rate of 8% simple interest per annum. If he paid an amount of $7176 to clear the loan, then find the time period of the loan.
(4) Calculate the amount due after 9 years if Michael borrowed a sum of $5300 at a rate of 10% simple interest.
(5) Daniel took a loan of $6200 at the rate of 6% simple interest per annum. If he paid an amount of $9548 to clear the loan, then find the time period of the loan.
(6) What amount does Robert have to pay after 5 years if he takes a loan of $3100 at 6% simple interest?
(7) How much loan did Barbara borrow 5 years ago at a rate of simple interest 5% per annum, if he paid $6937.5 to clear it?
(8) Calculate the amount due after 10 years if William borrowed a sum of $5500 at a rate of 9% simple interest.
(9) Calculate the amount due after 10 years if Susan borrowed a sum of $5650 at a rate of 5% simple interest.
(10) What amount does Linda have to pay after 6 years if he takes a loan of $3350 at 5% simple interest?