Simple Interest
Math MCQs

Question :  ( 1 of 10 )  What amount does Jessica have to pay after 5 years if he takes a loan of $3750 at 10% simple interest?

Correct Answer  $5625

Solution & Explanation

Solution

Given,

Principal (P) = $3750

Rate of Simple Interest (SI) = 10%

Time (t) = 5 years

Thus, Amount (A) = ?

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

Thus, here 10% simple interest means, Rate of Simple Interest (SI) is 10% 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) = $3750 × 10% × 5

= $3750 ×¹⁰/₁₀₀ × 5

= ^{3750 × 10 × 5}/₁₀₀

= ^{37500 × 5}/₁₀₀

= ¹⁸⁷⁵⁰⁰/₁₀₀

= $1875

Thus, Simple Interest = $1875

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 = $3750 + $1875

= $5625

Thus, Amount to be paid = $5625 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 = $3750

Rate of Simple Interest (SI) or (R) = 10%

And, Time (t) = 5 years

Thus, Amount (A)

= $3750 + ($3750 × 10% × 5)

= $3750 + ($3750 ×¹⁰/₁₀₀ × 5)

= $3750 + (^{3750 × 10 × 5}/₁₀₀)

= $3750 + (^{37500 × 5}/₁₀₀)

= $3750 + (¹⁸⁷⁵⁰⁰/₁₀₀)

= $3750 + $1875 = $5625

Thus, Amount (A) to be paid = $5625 Answer

Method (3) Unitary Method

Calculation of Amount using Unitary Method

Calculation of Interest using Unitary Method

Here, given Rate of Simple Interest = 10%

This, means, $10 per $100 per year

∵ For $100, the simple interest for 1 year = $10

∴ For $1, the simple interest for 1 year = ¹⁰/₁₀₀

∴ For $3750, the simple interest in 1 year

= ¹⁰/₁₀₀ × 3750

= ^{10 × 3750}/₁₀₀

= ³⁷⁵⁰⁰/₁₀₀ = $375

Thus, simple interest for 1 year = $375

Therefore, simple interest for 5 years

= Simple interest for 1 year × 5

= $375 × 5 = $1875

Thus, Simple Interest (SI) = $1875

Calculation of Amount

Amount = Principal + Interest

Thus, Amount = $3750 + $1875

= $5625

Thus, Amount to be paid = $5625 Answer

Similar Questions

(1) In how much time a principal of $3000 will amount to $3240 at a simple interest of 4% per annum?

(2) Calculate the amount due after 9 years if Thomas borrowed a sum of $5800 at a rate of 10% simple interest.

(3) Kimberly had to pay $5068.5 in order to furnish the loan taken 3 years before. If the rate of simple interest was 3% then find the sum borrowed.

(4) Find the amount to be paid if Barbara borrowed a sum of $5550 at 3% simple interest for 8 years.

(5) If Mark paid $4752 to settle his loan which he had taken 4 years before at a simple interest of 2%, then find the loan taken.

(6) How much loan did Donna borrow 5 years ago at a rate of simple interest 2% per annum, if he paid $7535 to clear it?

(7) James took a loan of $4000 at the rate of 6% simple interest per annum. If he paid an amount of $6400 to clear the loan, then find the time period of the loan.

(8) William had to pay $3710 in order to furnish the loan taken 3 years before. If the rate of simple interest was 2% then find the sum borrowed.

(9) What amount does Charles have to pay after 6 years if he takes a loan of $3900 at 7% simple interest?

(10) Jennifer took a loan of $4500 at the rate of 9% simple interest per annum. If he paid an amount of $8550 to clear the loan, then find the time period of the loan.