Question:
What amount will be due after 2 years if Robert borrowed a sum of $3050 at a 5% simple interest?
Correct Answer
$3355
Solution And Explanation
Solution
Given,
Principal (P) = $3050
Rate of Simple Interest (SI) = 5%
Time (t) = 2 years
Thus, Amount (A) = ?
The Rate of Interest is always calculated per annum, i.e. per year.
Thus, here 5% simple interest means, Rate of Simple Interest (SI) is 5% 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 × 5% × 2
= $3050 ×5/100 × 2
= 3050 × 5 × 2/100
= 15250 × 2/100
= 30500/100
= $305
Thus, Simple Interest = $305
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 + $305
= $3355
Thus, Amount to be paid = $3355 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) = 5%
And, Time (t) = 2 years
Thus, Amount (A)
= $3050 + ($3050 × 5% × 2)
= $3050 + ($3050 ×5/100 × 2)
= $3050 + (3050 × 5 × 2/100)
= $3050 + (15250 × 2/100)
= $3050 + (30500/100)
= $3050 + $305 = $3355
Thus, Amount (A) to be paid = $3355 Answer
Method (3) Unitary Method
Calculation of Amount using Unitary Method
Calculation of Interest using Unitary Method
Here, given Rate of Simple Interest = 5%
This, means, $5 per $100 per year
∵ For $100, the simple interest for 1 year = $5
∴ For $1, the simple interest for 1 year = 5/100
∴ For $3050, the simple interest in 1 year
= 5/100 × 3050
= 5 × 3050/100
= 15250/100 = $152.5
Thus, simple interest for 1 year = $152.5
Therefore, simple interest for 2 years
= Simple interest for 1 year × 2
= $152.5 × 2 = $305
Thus, Simple Interest (SI) = $305
Calculation of Amount
Amount = Principal + Interest
Thus, Amount = $3050 + $305
= $3355
Thus, Amount to be paid = $3355 Answer
Similar Questions
(1) If Margaret paid $5046 to settle his loan which he had taken 4 years before at a simple interest of 4%, then find the loan taken.
(2) Find the amount to be paid if Susan borrowed a sum of $5650 at 3% simple interest for 7 years.
(3) John took a loan of $4400 at the rate of 8% simple interest per annum. If he paid an amount of $6512 to clear the loan, then find the time period of the loan.
(4) Sarah took a loan of $5700 at the rate of 10% simple interest per annum. If he paid an amount of $11400 to clear the loan, then find the time period of the loan.
(5) Find the amount to be paid if Jennifer borrowed a sum of $5250 at 7% simple interest for 8 years.
(6) Calculate the amount due after 9 years if Elizabeth borrowed a sum of $5450 at a rate of 3% simple interest.
(7) Calculate the amount due if David borrowed a sum of $3400 at 2% simple interest for 3 years.
(8) Mary took a loan of $4100 at the rate of 8% simple interest per annum. If he paid an amount of $6068 to clear the loan, then find the time period of the loan.
(9) Lisa took a loan of $6100 at the rate of 9% simple interest per annum. If he paid an amount of $9943 to clear the loan, then find the time period of the loan.
(10) Susan took a loan of $5300 at the rate of 7% simple interest per annum. If he paid an amount of $7526 to clear the loan, then find the time period of the loan.