Question:
If Mary borrowed $3050 from a bank at a rate of 3% simple interest per annum then find the amount to be paid after 2 years.
Correct Answer
$3233
Solution And Explanation
Solution
Given,
Principal (P) = $3050
Rate of Simple Interest (SI) = 3%
Time (t) = 2 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) = $3050 × 3% × 2
= $3050 ×3/100 × 2
= 3050 × 3 × 2/100
= 9150 × 2/100
= 18300/100
= $183
Thus, Simple Interest = $183
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 = $3050 + $183
= $3233
Thus, Amount to be paid = $3233 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 = $3050
Rate of Simple Interest (SI) or (R) = 3%
And, Time (t) = 2 years
Thus, Amount (A)
= $3050 + ($3050 × 3% × 2)
= $3050 + ($3050 ×3/100 × 2)
= $3050 + (3050 × 3 × 2/100)
= $3050 + (9150 × 2/100)
= $3050 + (18300/100)
= $3050 + $183 = $3233
Thus, Amount (A) to be paid = $3233 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 $3050, the simple interest in 1 year
= 3/100 × 3050
= 3 × 3050/100
= 9150/100 = $91.5
Thus, simple interest for 1 year = $91.5
Therefore, simple interest for 2 years
= Simple interest for 1 year × 2
= $91.5 × 2 = $183
Thus, Simple Interest (SI) = $183
Calculation of Amount
Amount = Principal + Interest
Thus, Amount = $3050 + $183
= $3233
Thus, Amount to be paid = $3233 Answer
Similar Questions
(1) Margaret had to pay $4872 in order to furnish the loan taken 3 years before. If the rate of simple interest was 4% then find the sum borrowed.
(2) Find the amount to be paid if Barbara borrowed a sum of $5550 at 6% simple interest for 8 years.
(3) What amount does Elizabeth have to pay after 5 years if he takes a loan of $3450 at 10% simple interest?
(4) Find the amount to be paid if John borrowed a sum of $5200 at 7% simple interest for 8 years.
(5) Calculate the amount due after 9 years if James borrowed a sum of $5000 at a rate of 10% simple interest.
(6) Christopher took a loan of $6000 at the rate of 6% simple interest per annum. If he paid an amount of $8160 to clear the loan, then find the time period of the loan.
(7) What amount will be due after 2 years if David borrowed a sum of $3200 at a 8% simple interest?
(8) Jennifer took a loan of $4500 at the rate of 10% simple interest per annum. If he paid an amount of $8100 to clear the loan, then find the time period of the loan.
(9) Find the amount to be paid if John borrowed a sum of $5200 at 8% simple interest for 8 years.
(10) What amount does Charles have to pay after 6 years if he takes a loan of $3900 at 7% simple interest?