Simple Interest
Math MCQs

Question :    Find the amount to be paid if Jessica borrowed a sum of $5750 at 6% simple interest for 7 years.

Correct Answer  $8165

Solution & Explanation

Solution

Given,

Principal (P) = $5750

Rate of Simple Interest (SI) = 6%

Time (t) = 7 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% × 7

= $5750 ×⁶/₁₀₀ × 7

= ^{5750 × 6 × 7}/₁₀₀

= ^{34500 × 7}/₁₀₀

= ²⁴¹⁵⁰⁰/₁₀₀

= $2415

Thus, Simple Interest = $2415

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 + $2415

= $8165

Thus, Amount to be paid = $8165 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) = 7 years

Thus, Amount (A)

= $5750 + ($5750 × 6% × 7)

= $5750 + ($5750 ×⁶/₁₀₀ × 7)

= $5750 + (^{5750 × 6 × 7}/₁₀₀)

= $5750 + (^{34500 × 7}/₁₀₀)

= $5750 + (²⁴¹⁵⁰⁰/₁₀₀)

= $5750 + $2415 = $8165

Thus, Amount (A) to be paid = $8165 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 7 years

= Simple interest for 1 year × 7

= $345 × 7 = $2415

Thus, Simple Interest (SI) = $2415

Calculation of Amount

Amount = Principal + Interest

Thus, Amount = $5750 + $2415

= $8165

Thus, Amount to be paid = $8165 Answer

Similar Questions

(1) Daniel took a loan of $6200 at the rate of 6% simple interest per annum. If he paid an amount of $9548 to clear the loan, then find the time period of the loan.

(2) In how much time a principal of $3200 will amount to $3680 at a simple interest of 3% per annum?

(3) What amount will be due after 2 years if Kenneth borrowed a sum of $4000 at a 7% simple interest?

(4) Calculate the amount due if Richard borrowed a sum of $3600 at 5% simple interest for 4 years.

(5) Margaret took a loan of $6700 at the rate of 8% simple interest per annum. If he paid an amount of $10452 to clear the loan, then find the time period of the loan.

(6) Sandra took a loan of $6900 at the rate of 7% simple interest per annum. If he paid an amount of $10281 to clear the loan, then find the time period of the loan.

(7) Find the amount to be paid if Susan borrowed a sum of $5650 at 6% simple interest for 8 years.

(8) Calculate the amount due after 10 years if James borrowed a sum of $5000 at a rate of 9% simple interest.

(9) If Matthew paid $4536 to settle his loan which he had taken 4 years before at a simple interest of 2%, then find the loan taken.

(10) Find the amount to be paid if David borrowed a sum of $5400 at 6% simple interest for 7 years.