Simple Interest
MCQs Math


Question:     Calculate the amount due after 9 years if Jessica borrowed a sum of $5750 at a rate of 4% simple interest.


Correct Answer  $7820

Solution And Explanation

Solution

Given,

Principal (P) = $5750

Rate of Simple Interest (SI) = 4%

Time (t) = 9 years

Thus, Amount (A) = ?

The Rate of Interest is always calculated per annum, i.e. per year.

Thus, here 4% simple interest means, Rate of Simple Interest (SI) is 4% 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) = $5750 × 4% × 9

= $5750 ×4/100 × 9

= 5750 × 4 × 9/100

= 23000 × 9/100

= 207000/100

= $2070

Thus, Simple Interest = $2070

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 = $5750 + $2070

= $7820

Thus, Amount to be paid = $7820 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 = $5750

Rate of Simple Interest (SI) or (R) = 4%

And, Time (t) = 9 years

Thus, Amount (A)

= $5750 + ($5750 × 4% × 9)

= $5750 + ($5750 ×4/100 × 9)

= $5750 + (5750 × 4 × 9/100)

= $5750 + (23000 × 9/100)

= $5750 + (207000/100)

= $5750 + $2070 = $7820

Thus, Amount (A) to be paid = $7820 Answer

Method (3) Unitary Method

Calculation of Amount using Unitary Method

Calculation of Interest using Unitary Method

Here, given Rate of Simple Interest = 4%

This, means, $4 per $100 per year

∵ For $100, the simple interest for 1 year = $4

∴ For $1, the simple interest for 1 year = 4/100

∴ For $5750, the simple interest in 1 year

= 4/100 × 5750

= 4 × 5750/100

= 23000/100 = $230

Thus, simple interest for 1 year = $230

Therefore, simple interest for 9 years

= Simple interest for 1 year × 9

= $230 × 9 = $2070

Thus, Simple Interest (SI) = $2070

Calculation of Amount

Amount = Principal + Interest

Thus, Amount = $5750 + $2070

= $7820

Thus, Amount to be paid = $7820 Answer


Similar Questions

(1) Karen took a loan of $5900 at the rate of 8% simple interest per annum. If he paid an amount of $9204 to clear the loan, then find the time period of the loan.

(2) If Paul paid $5640 to settle his loan which he had taken 4 years before at a simple interest of 5%, then find the loan taken.

(3) Calculate the amount due if David borrowed a sum of $3400 at 5% simple interest for 3 years.

(4) If Donna paid $5238 to settle his loan which he had taken 4 years before at a simple interest of 2%, then find the loan taken.

(5) Find the amount to be paid if Mary borrowed a sum of $5050 at 3% simple interest for 8 years.

(6) Calculate the amount due after 9 years if Elizabeth borrowed a sum of $5450 at a rate of 8% simple interest.

(7) How much loan did Kenneth borrow 5 years ago at a rate of simple interest 4% per annum, if he paid $8400 to clear it?

(8) John took a loan of $4400 at the rate of 10% simple interest per annum. If he paid an amount of $8800 to clear the loan, then find the time period of the loan.

(9) How much loan did Margaret borrow 5 years ago at a rate of simple interest 4% per annum, if he paid $7620 to clear it?

(10) What amount does Susan have to pay after 5 years if he takes a loan of $3650 at 7% simple interest?


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