Simple Interest
Math MCQs

Question :  ( 1 of 10 )  What amount will be due after 2 years if Anthony borrowed a sum of $3650 at a 8% simple interest?

Correct Answer  $4234

Solution & Explanation

Solution

Given,

Principal (P) = $3650

Rate of Simple Interest (SI) = 8%

Time (t) = 2 years

Thus, Amount (A) = ?

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

Thus, here 8% simple interest means, Rate of Simple Interest (SI) is 8% 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) = $3650 × 8% × 2

= $3650 ×⁸/₁₀₀ × 2

= ^{3650 × 8 × 2}/₁₀₀

= ^{29200 × 2}/₁₀₀

= ⁵⁸⁴⁰⁰/₁₀₀

= $584

Thus, Simple Interest = $584

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 = $3650 + $584

= $4234

Thus, Amount to be paid = $4234 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 = $3650

Rate of Simple Interest (SI) or (R) = 8%

And, Time (t) = 2 years

Thus, Amount (A)

= $3650 + ($3650 × 8% × 2)

= $3650 + ($3650 ×⁸/₁₀₀ × 2)

= $3650 + (^{3650 × 8 × 2}/₁₀₀)

= $3650 + (^{29200 × 2}/₁₀₀)

= $3650 + (⁵⁸⁴⁰⁰/₁₀₀)

= $3650 + $584 = $4234

Thus, Amount (A) to be paid = $4234 Answer

Method (3) Unitary Method

Calculation of Amount using Unitary Method

Calculation of Interest using Unitary Method

Here, given Rate of Simple Interest = 8%

This, means, $8 per $100 per year

∵ For $100, the simple interest for 1 year = $8

∴ For $1, the simple interest for 1 year = ⁸/₁₀₀

∴ For $3650, the simple interest in 1 year

= ⁸/₁₀₀ × 3650

= ^{8 × 3650}/₁₀₀

= ²⁹²⁰⁰/₁₀₀ = $292

Thus, simple interest for 1 year = $292

Therefore, simple interest for 2 years

= Simple interest for 1 year × 2

= $292 × 2 = $584

Thus, Simple Interest (SI) = $584

Calculation of Amount

Amount = Principal + Interest

Thus, Amount = $3650 + $584

= $4234

Thus, Amount to be paid = $4234 Answer

Similar Questions

(1) Calculate the amount due after 9 years if Mary borrowed a sum of $5050 at a rate of 4% simple interest.

(2) Michael took a loan of $4600 at the rate of 7% simple interest per annum. If he paid an amount of $6854 to clear the loan, then find the time period of the loan.

(3) Calculate the amount due if Patricia borrowed a sum of $3150 at 7% simple interest for 4 years.

(4) Find the amount to be paid if David borrowed a sum of $5400 at 2% simple interest for 8 years.

(5) Christopher took a loan of $6000 at the rate of 7% simple interest per annum. If he paid an amount of $8520 to clear the loan, then find the time period of the loan.

(6) Calculate the amount due after 9 years if Joseph borrowed a sum of $5700 at a rate of 3% simple interest.

(7) Calculate the amount due after 9 years if Barbara borrowed a sum of $5550 at a rate of 7% simple interest.

(8) Margaret took a loan of $6700 at the rate of 8% simple interest per annum. If he paid an amount of $11524 to clear the loan, then find the time period of the loan.

(9) If Daniel paid $4756 to settle his loan which he had taken 4 years before at a simple interest of 4%, then find the loan taken.

(10) William took a loan of $5000 at the rate of 6% simple interest per annum. If he paid an amount of $7100 to clear the loan, then find the time period of the loan.