Simple Interest
Math MCQs

Question :    Calculate the amount due after 10 years if James borrowed a sum of $5000 at a rate of 10% simple interest.

Correct Answer  $10000

Solution & Explanation

Solution

Given,

Principal (P) = $5000

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) = $5000 × 10% × 10

= $5000 ×¹⁰/₁₀₀ × 10

= ^{5000 × 10 × 10}/₁₀₀

= ^{50000 × 10}/₁₀₀

= ⁵⁰⁰⁰⁰⁰/₁₀₀

= $5000

Thus, Simple Interest = $5000

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 = $5000 + $5000

= $10000

Thus, Amount to be paid = $10000 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 = $5000

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

And, Time (t) = 10 years

Thus, Amount (A)

= $5000 + ($5000 × 10% × 10)

= $5000 + ($5000 ×¹⁰/₁₀₀ × 10)

= $5000 + (^{5000 × 10 × 10}/₁₀₀)

= $5000 + (^{50000 × 10}/₁₀₀)

= $5000 + (⁵⁰⁰⁰⁰⁰/₁₀₀)

= $5000 + $5000 = $10000

Thus, Amount (A) to be paid = $10000 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 $5000, the simple interest in 1 year

= ¹⁰/₁₀₀ × 5000

= ^{10 × 5000}/₁₀₀

= ⁵⁰⁰⁰⁰/₁₀₀ = $500

Thus, simple interest for 1 year = $500

Therefore, simple interest for 10 years

= Simple interest for 1 year × 10

= $500 × 10 = $5000

Thus, Simple Interest (SI) = $5000

Calculation of Amount

Amount = Principal + Interest

Thus, Amount = $5000 + $5000

= $10000

Thus, Amount to be paid = $10000 Answer

Similar Questions

(1) Find the amount to be paid if Joseph borrowed a sum of $5700 at 10% simple interest for 8 years.

(2) Calculate the amount due after 10 years if Jennifer borrowed a sum of $5250 at a rate of 4% simple interest.

(3) William took a loan of $5000 at the rate of 8% simple interest per annum. If he paid an amount of $8200 to clear the loan, then find the time period of the loan.

(4) If Nancy paid $4980 to settle his loan which he had taken 4 years before at a simple interest of 5%, then find the loan taken.

(5) Jennifer took a loan of $4500 at the rate of 7% simple interest per annum. If he paid an amount of $7335 to clear the loan, then find the time period of the loan.

(6) Calculate the amount due if Jessica borrowed a sum of $3750 at 7% simple interest for 4 years.

(7) Anthony took a loan of $6600 at the rate of 9% simple interest per annum. If he paid an amount of $10758 to clear the loan, then find the time period of the loan.

(8) How much loan did Timothy borrow 5 years ago at a rate of simple interest 4% per annum, if he paid $8880 to clear it?

(9) Calculate the amount due if Joseph borrowed a sum of $3700 at 10% simple interest for 3 years.

(10) In how much time a principal of $3000 will amount to $3450 at a simple interest of 5% per annum?