Question:
What amount will be due after 2 years if Joshua borrowed a sum of $3950 at a 5% simple interest?
Correct Answer
$4345
Solution And Explanation
Solution
Given,
Principal (P) = $3950
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) = $3950 × 5% × 2
= $3950 ×5/100 × 2
= 3950 × 5 × 2/100
= 19750 × 2/100
= 39500/100
= $395
Thus, Simple Interest = $395
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 = $3950 + $395
= $4345
Thus, Amount to be paid = $4345 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 = $3950
Rate of Simple Interest (SI) or (R) = 5%
And, Time (t) = 2 years
Thus, Amount (A)
= $3950 + ($3950 × 5% × 2)
= $3950 + ($3950 ×5/100 × 2)
= $3950 + (3950 × 5 × 2/100)
= $3950 + (19750 × 2/100)
= $3950 + (39500/100)
= $3950 + $395 = $4345
Thus, Amount (A) to be paid = $4345 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 $3950, the simple interest in 1 year
= 5/100 × 3950
= 5 × 3950/100
= 19750/100 = $197.5
Thus, simple interest for 1 year = $197.5
Therefore, simple interest for 2 years
= Simple interest for 1 year × 2
= $197.5 × 2 = $395
Thus, Simple Interest (SI) = $395
Calculation of Amount
Amount = Principal + Interest
Thus, Amount = $3950 + $395
= $4345
Thus, Amount to be paid = $4345 Answer
Similar Questions
(1) What amount will be due after 2 years if John borrowed a sum of $3100 at a 9% simple interest?
(2) Calculate the amount due if Charles borrowed a sum of $3900 at 4% simple interest for 4 years.
(3) Lisa took a loan of $6100 at the rate of 7% simple interest per annum. If he paid an amount of $8662 to clear the loan, then find the time period of the loan.
(4) Find the amount to be paid if John borrowed a sum of $5200 at 7% simple interest for 7 years.
(5) Michael took a loan of $4600 at the rate of 9% simple interest per annum. If he paid an amount of $8326 to clear the loan, then find the time period of the loan.
(6) Barbara took a loan of $5100 at the rate of 9% simple interest per annum. If he paid an amount of $9690 to clear the loan, then find the time period of the loan.
(7) What amount does Charles have to pay after 6 years if he takes a loan of $3900 at 8% simple interest?
(8) Calculate the amount due after 10 years if Patricia borrowed a sum of $5150 at a rate of 10% simple interest.
(9) Calculate the amount due after 9 years if Barbara borrowed a sum of $5550 at a rate of 10% simple interest.
(10) Calculate the amount due after 10 years if Sarah borrowed a sum of $5850 at a rate of 4% simple interest.