Simple Interest
Math MCQs

Question :  ( 1 of 10 )  Calculate the amount due after 10 years if Thomas borrowed a sum of $5800 at a rate of 10% simple interest.

Correct Answer  $11600

Solution & Explanation

Solution

Given,

Principal (P) = $5800

Rate of Simple Interest (SI) = 10%

Time (t) = 10 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) = $5800 × 10% × 10

= $5800 ×¹⁰/₁₀₀ × 10

= ^{5800 × 10 × 10}/₁₀₀

= ^{58000 × 10}/₁₀₀

= ⁵⁸⁰⁰⁰⁰/₁₀₀

= $5800

Thus, Simple Interest = $5800

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 + $5800

= $11600

Thus, Amount to be paid = $11600 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) = 10%

And, Time (t) = 10 years

Thus, Amount (A)

= $5800 + ($5800 × 10% × 10)

= $5800 + ($5800 ×¹⁰/₁₀₀ × 10)

= $5800 + (^{5800 × 10 × 10}/₁₀₀)

= $5800 + (^{58000 × 10}/₁₀₀)

= $5800 + (⁵⁸⁰⁰⁰⁰/₁₀₀)

= $5800 + $5800 = $11600

Thus, Amount (A) to be paid = $11600 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 $5800, the simple interest in 1 year

= ¹⁰/₁₀₀ × 5800

= ^{10 × 5800}/₁₀₀

= ⁵⁸⁰⁰⁰/₁₀₀ = $580

Thus, simple interest for 1 year = $580

Therefore, simple interest for 10 years

= Simple interest for 1 year × 10

= $580 × 10 = $5800

Thus, Simple Interest (SI) = $5800

Calculation of Amount

Amount = Principal + Interest

Thus, Amount = $5800 + $5800

= $11600

Thus, Amount to be paid = $11600 Answer

Similar Questions

(1) What amount will be due after 2 years if Kenneth borrowed a sum of $4000 at a 4% simple interest?

(2) Jennifer took a loan of $4500 at the rate of 7% simple interest per annum. If he paid an amount of $7650 to clear the loan, then find the time period of the loan.

(3) Find the amount to be paid if John borrowed a sum of $5200 at 9% simple interest for 7 years.

(4) Calculate the amount due after 9 years if Karen borrowed a sum of $5950 at a rate of 3% simple interest.

(5) Calculate the amount due after 10 years if Barbara borrowed a sum of $5550 at a rate of 2% simple interest.

(6) What amount does Mary have to pay after 6 years if he takes a loan of $3050 at 9% simple interest?

(7) Calculate the amount due after 10 years if Elizabeth borrowed a sum of $5450 at a rate of 3% simple interest.

(8) Find the amount to be paid if John borrowed a sum of $5200 at 4% simple interest for 7 years.

(9) 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.

(10) Find the amount to be paid if Elizabeth borrowed a sum of $5450 at 8% simple interest for 7 years.