Question:
What amount will be due after 2 years if Robert borrowed a sum of $3050 at a 10% simple interest?
Correct Answer
$3660
Solution And Explanation
Solution
Given,
Principal (P) = $3050
Rate of Simple Interest (SI) = 10%
Time (t) = 2 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) = $3050 × 10% × 2
= $3050 ×10/100 × 2
= 3050 × 10 × 2/100
= 30500 × 2/100
= 61000/100
= $610
Thus, Simple Interest = $610
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 + $610
= $3660
Thus, Amount to be paid = $3660 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) = 10%
And, Time (t) = 2 years
Thus, Amount (A)
= $3050 + ($3050 × 10% × 2)
= $3050 + ($3050 ×10/100 × 2)
= $3050 + (3050 × 10 × 2/100)
= $3050 + (30500 × 2/100)
= $3050 + (61000/100)
= $3050 + $610 = $3660
Thus, Amount (A) to be paid = $3660 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 $3050, the simple interest in 1 year
= 10/100 × 3050
= 10 × 3050/100
= 30500/100 = $305
Thus, simple interest for 1 year = $305
Therefore, simple interest for 2 years
= Simple interest for 1 year × 2
= $305 × 2 = $610
Thus, Simple Interest (SI) = $610
Calculation of Amount
Amount = Principal + Interest
Thus, Amount = $3050 + $610
= $3660
Thus, Amount to be paid = $3660 Answer
Similar Questions
(1) Joseph took a loan of $5400 at the rate of 10% simple interest per annum. If he paid an amount of $9180 to clear the loan, then find the time period of the loan.
(2) Calculate the amount due if Richard borrowed a sum of $3600 at 3% simple interest for 3 years.
(3) Calculate the amount due after 9 years if Karen borrowed a sum of $5950 at a rate of 4% simple interest.
(4) In how much time a principal of $3000 will amount to $3270 at a simple interest of 3% per annum?
(5) Jennifer took a loan of $4500 at the rate of 6% simple interest per annum. If he paid an amount of $6660 to clear the loan, then find the time period of the loan.
(6) If James paid $3360 to settle his loan which he had taken 4 years before at a simple interest of 3%, then find the loan taken.
(7) If Donald paid $5040 to settle his loan which he had taken 4 years before at a simple interest of 3%, then find the loan taken.
(8) Joshua had to pay $5341 in order to furnish the loan taken 3 years before. If the rate of simple interest was 3% then find the sum borrowed.
(9) Calculate the amount due after 10 years if Mary borrowed a sum of $5050 at a rate of 8% simple interest.
(10) Calculate the amount due if Robert borrowed a sum of $3100 at 3% simple interest for 4 years.