Question:
Calculate the amount due if David borrowed a sum of $3400 at 2% simple interest for 4 years.
Correct Answer
$3672
Solution And Explanation
Solution
Given,
Principal (P) = $3400
Rate of Simple Interest (SI) = 2%
Time (t) = 4 years
Thus, Amount (A) = ?
The Rate of Interest is always calculated per annum, i.e. per year.
Thus, here 2% simple interest means, Rate of Simple Interest (SI) is 2% 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) = $3400 × 2% × 4
= $3400 ×2/100 × 4
= 3400 × 2 × 4/100
= 6800 × 4/100
= 27200/100
= $272
Thus, Simple Interest = $272
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 = $3400 + $272
= $3672
Thus, Amount to be paid = $3672 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 = $3400
Rate of Simple Interest (SI) or (R) = 2%
And, Time (t) = 4 years
Thus, Amount (A)
= $3400 + ($3400 × 2% × 4)
= $3400 + ($3400 ×2/100 × 4)
= $3400 + (3400 × 2 × 4/100)
= $3400 + (6800 × 4/100)
= $3400 + (27200/100)
= $3400 + $272 = $3672
Thus, Amount (A) to be paid = $3672 Answer
Method (3) Unitary Method
Calculation of Amount using Unitary Method
Calculation of Interest using Unitary Method
Here, given Rate of Simple Interest = 2%
This, means, $2 per $100 per year
∵ For $100, the simple interest for 1 year = $2
∴ For $1, the simple interest for 1 year = 2/100
∴ For $3400, the simple interest in 1 year
= 2/100 × 3400
= 2 × 3400/100
= 6800/100 = $68
Thus, simple interest for 1 year = $68
Therefore, simple interest for 4 years
= Simple interest for 1 year × 4
= $68 × 4 = $272
Thus, Simple Interest (SI) = $272
Calculation of Amount
Amount = Principal + Interest
Thus, Amount = $3400 + $272
= $3672
Thus, Amount to be paid = $3672 Answer
Similar Questions
(1) Christopher took a loan of $6000 at the rate of 10% simple interest per annum. If he paid an amount of $10800 to clear the loan, then find the time period of the loan.
(2) How much loan did Sharon borrow 5 years ago at a rate of simple interest 4% per annum, if he paid $9300 to clear it?
(3) What amount does Richard have to pay after 6 years if he takes a loan of $3600 at 9% simple interest?
(4) Nancy took a loan of $6300 at the rate of 7% simple interest per annum. If he paid an amount of $9828 to clear the loan, then find the time period of the loan.
(5) If Charles borrowed $3900 from a bank at a rate of 2% simple interest per annum then find the amount to be paid after 2 years.
(6) Margaret took a loan of $6700 at the rate of 9% simple interest per annum. If he paid an amount of $10921 to clear the loan, then find the time period of the loan.
(7) If Daniel paid $4756 to settle his loan which he had taken 4 years before at a simple interest of 4%, then find the loan taken.
(8) Emily had to pay $5035 in order to furnish the loan taken 3 years before. If the rate of simple interest was 2% then find the sum borrowed.
(9) Find the amount to be paid if Joseph borrowed a sum of $5700 at 6% simple interest for 8 years.
(10) John took a loan of $4400 at the rate of 10% simple interest per annum. If he paid an amount of $7920 to clear the loan, then find the time period of the loan.