Simple Interest
Math MCQs

Question :    Find the amount to be paid if Jessica borrowed a sum of $5750 at 6% simple interest for 8 years.

Correct Answer  $8510

Solution & Explanation

Solution

Given,

Principal (P) = $5750

Rate of Simple Interest (SI) = 6%

Time (t) = 8 years

Thus, Amount (A) = ?

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

Thus, here 6% simple interest means, Rate of Simple Interest (SI) is 6% 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) = $5750 × 6% × 8

= $5750 ×⁶/₁₀₀ × 8

= ^{5750 × 6 × 8}/₁₀₀

= ^{34500 × 8}/₁₀₀

= ²⁷⁶⁰⁰⁰/₁₀₀

= $2760

Thus, Simple Interest = $2760

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 = $5750 + $2760

= $8510

Thus, Amount to be paid = $8510 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 = $5750

Rate of Simple Interest (SI) or (R) = 6%

And, Time (t) = 8 years

Thus, Amount (A)

= $5750 + ($5750 × 6% × 8)

= $5750 + ($5750 ×⁶/₁₀₀ × 8)

= $5750 + (^{5750 × 6 × 8}/₁₀₀)

= $5750 + (^{34500 × 8}/₁₀₀)

= $5750 + (²⁷⁶⁰⁰⁰/₁₀₀)

= $5750 + $2760 = $8510

Thus, Amount (A) to be paid = $8510 Answer

Method (3) Unitary Method

Calculation of Amount using Unitary Method

Calculation of Interest using Unitary Method

Here, given Rate of Simple Interest = 6%

This, means, $6 per $100 per year

∵ For $100, the simple interest for 1 year = $6

∴ For $1, the simple interest for 1 year = ⁶/₁₀₀

∴ For $5750, the simple interest in 1 year

= ⁶/₁₀₀ × 5750

= ^{6 × 5750}/₁₀₀

= ³⁴⁵⁰⁰/₁₀₀ = $345

Thus, simple interest for 1 year = $345

Therefore, simple interest for 8 years

= Simple interest for 1 year × 8

= $345 × 8 = $2760

Thus, Simple Interest (SI) = $2760

Calculation of Amount

Amount = Principal + Interest

Thus, Amount = $5750 + $2760

= $8510

Thus, Amount to be paid = $8510 Answer

Similar Questions

(1) How much loan did Cynthia borrow 5 years ago at a rate of simple interest 2% per annum, if he paid $8745 to clear it?

(2) If David borrowed $3400 from a bank at a rate of 2% simple interest per annum then find the amount to be paid after 2 years.

(3) Michael had to pay $3597 in order to furnish the loan taken 3 years before. If the rate of simple interest was 3% then find the sum borrowed.

(4) Calculate the amount due if Susan borrowed a sum of $3650 at 5% simple interest for 4 years.

(5) Betty took a loan of $6500 at the rate of 6% simple interest per annum. If he paid an amount of $9620 to clear the loan, then find the time period of the loan.

(6) Calculate the amount due if Joseph borrowed a sum of $3700 at 7% simple interest for 4 years.

(7) Calculate the amount due after 9 years if Susan borrowed a sum of $5650 at a rate of 7% simple interest.

(8) Sandra took a loan of $6900 at the rate of 9% simple interest per annum. If he paid an amount of $11868 to clear the loan, then find the time period of the loan.

(9) What amount does Patricia have to pay after 6 years if he takes a loan of $3150 at 3% simple interest?

(10) If Kimberly paid $5208 to settle his loan which he had taken 4 years before at a simple interest of 3%, then find the loan taken.