Simple Interest
Math MCQs

Question :    Calculate the amount due after 10 years if Thomas borrowed a sum of $5800 at a rate of 3% simple interest.

Correct Answer  $7540

Solution & Explanation

Solution

Given,

Principal (P) = $5800

Rate of Simple Interest (SI) = 3%

Time (t) = 10 years

Thus, Amount (A) = ?

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

Thus, here 3% simple interest means, Rate of Simple Interest (SI) is 3% 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) = $5800 × 3% × 10

= $5800 ׳/₁₀₀ × 10

= ^{5800 × 3 × 10}/₁₀₀

= ^{17400 × 10}/₁₀₀

= ¹⁷⁴⁰⁰⁰/₁₀₀

= $1740

Thus, Simple Interest = $1740

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 = $5800 + $1740

= $7540

Thus, Amount to be paid = $7540 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 = $5800

Rate of Simple Interest (SI) or (R) = 3%

And, Time (t) = 10 years

Thus, Amount (A)

= $5800 + ($5800 × 3% × 10)

= $5800 + ($5800 ׳/₁₀₀ × 10)

= $5800 + (^{5800 × 3 × 10}/₁₀₀)

= $5800 + (^{17400 × 10}/₁₀₀)

= $5800 + (¹⁷⁴⁰⁰⁰/₁₀₀)

= $5800 + $1740 = $7540

Thus, Amount (A) to be paid = $7540 Answer

Method (3) Unitary Method

Calculation of Amount using Unitary Method

Calculation of Interest using Unitary Method

Here, given Rate of Simple Interest = 3%

This, means, $3 per $100 per year

∵ For $100, the simple interest for 1 year = $3

∴ For $1, the simple interest for 1 year = ³/₁₀₀

∴ For $5800, the simple interest in 1 year

= ³/₁₀₀ × 5800

= ^{3 × 5800}/₁₀₀

= ¹⁷⁴⁰⁰/₁₀₀ = $174

Thus, simple interest for 1 year = $174

Therefore, simple interest for 10 years

= Simple interest for 1 year × 10

= $174 × 10 = $1740

Thus, Simple Interest (SI) = $1740

Calculation of Amount

Amount = Principal + Interest

Thus, Amount = $5800 + $1740

= $7540

Thus, Amount to be paid = $7540 Answer

Similar Questions

(1) What amount does Linda have to pay after 6 years if he takes a loan of $3350 at 5% simple interest?

(2) What amount will be due after 2 years if Christopher borrowed a sum of $3500 at a 6% simple interest?

(3) Calculate the amount due after 10 years if Jennifer borrowed a sum of $5250 at a rate of 7% simple interest.

(4) Karen took a loan of $5900 at the rate of 8% simple interest per annum. If he paid an amount of $8732 to clear the loan, then find the time period of the loan.

(5) Calculate the amount due if Karen borrowed a sum of $3950 at 5% simple interest for 4 years.

(6) Linda took a loan of $4700 at the rate of 7% simple interest per annum. If he paid an amount of $6674 to clear the loan, then find the time period of the loan.

(7) Michael took a loan of $4600 at the rate of 6% simple interest per annum. If he paid an amount of $6532 to clear the loan, then find the time period of the loan.

(8) Robert had to pay $3286 in order to furnish the loan taken 3 years before. If the rate of simple interest was 2% then find the sum borrowed.

(9) Calculate the amount due after 9 years if Susan borrowed a sum of $5650 at a rate of 8% simple interest.

(10) If Lisa paid $4374 to settle his loan which he had taken 4 years before at a simple interest of 2%, then find the loan taken.