Simple Interest
Math MCQs

Question :  ( 1 of 10 )  Calculate the amount due after 10 years if Jennifer borrowed a sum of $5250 at a rate of 9% simple interest.

Correct Answer  $9975

Solution & Explanation

Solution

Given,

Principal (P) = $5250

Rate of Simple Interest (SI) = 9%

Time (t) = 10 years

Thus, Amount (A) = ?

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

Thus, here 9% simple interest means, Rate of Simple Interest (SI) is 9% 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) = $5250 × 9% × 10

= $5250 ×⁹/₁₀₀ × 10

= ^{5250 × 9 × 10}/₁₀₀

= ^{47250 × 10}/₁₀₀

= ⁴⁷²⁵⁰⁰/₁₀₀

= $4725

Thus, Simple Interest = $4725

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 = $5250 + $4725

= $9975

Thus, Amount to be paid = $9975 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 = $5250

Rate of Simple Interest (SI) or (R) = 9%

And, Time (t) = 10 years

Thus, Amount (A)

= $5250 + ($5250 × 9% × 10)

= $5250 + ($5250 ×⁹/₁₀₀ × 10)

= $5250 + (^{5250 × 9 × 10}/₁₀₀)

= $5250 + (^{47250 × 10}/₁₀₀)

= $5250 + (⁴⁷²⁵⁰⁰/₁₀₀)

= $5250 + $4725 = $9975

Thus, Amount (A) to be paid = $9975 Answer

Method (3) Unitary Method

Calculation of Amount using Unitary Method

Calculation of Interest using Unitary Method

Here, given Rate of Simple Interest = 9%

This, means, $9 per $100 per year

∵ For $100, the simple interest for 1 year = $9

∴ For $1, the simple interest for 1 year = ⁹/₁₀₀

∴ For $5250, the simple interest in 1 year

= ⁹/₁₀₀ × 5250

= ^{9 × 5250}/₁₀₀

= ⁴⁷²⁵⁰/₁₀₀ = $472.5

Thus, simple interest for 1 year = $472.5

Therefore, simple interest for 10 years

= Simple interest for 1 year × 10

= $472.5 × 10 = $4725

Thus, Simple Interest (SI) = $4725

Calculation of Amount

Amount = Principal + Interest

Thus, Amount = $5250 + $4725

= $9975

Thus, Amount to be paid = $9975 Answer

Similar Questions

(1) Sandra had to pay $4850.5 in order to furnish the loan taken 3 years before. If the rate of simple interest was 3% then find the sum borrowed.

(2) Calculate the amount due after 9 years if Barbara borrowed a sum of $5550 at a rate of 6% simple interest.

(3) Thomas took a loan of $5600 at the rate of 7% simple interest per annum. If he paid an amount of $8344 to clear the loan, then find the time period of the loan.

(4) Calculate the amount due after 10 years if James borrowed a sum of $5000 at a rate of 2% simple interest.

(5) Mark had to pay $4928 in order to furnish the loan taken 3 years before. If the rate of simple interest was 4% then find the sum borrowed.

(6) Mary took a loan of $4100 at the rate of 9% simple interest per annum. If he paid an amount of $6683 to clear the loan, then find the time period of the loan.

(7) What amount does Karen have to pay after 5 years if he takes a loan of $3950 at 2% simple interest?

(8) How much loan did Steven borrow 5 years ago at a rate of simple interest 5% per annum, if he paid $8250 to clear it?

(9) Jessica had to pay $4087.5 in order to furnish the loan taken 3 years before. If the rate of simple interest was 3% then find the sum borrowed.

(10) What amount does Jessica have to pay after 6 years if he takes a loan of $3750 at 8% simple interest?