Simple Interest
Math MCQs

Question :    What amount does Joseph have to pay after 6 years if he takes a loan of $3700 at 6% simple interest?

Correct Answer  $5032

Solution & Explanation

Solution

Given,

Principal (P) = $3700

Rate of Simple Interest (SI) = 6%

Time (t) = 6 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) = $3700 × 6% × 6

= $3700 ×⁶/₁₀₀ × 6

= ^{3700 × 6 × 6}/₁₀₀

= ^{22200 × 6}/₁₀₀

= ¹³³²⁰⁰/₁₀₀

= $1332

Thus, Simple Interest = $1332

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 = $3700 + $1332

= $5032

Thus, Amount to be paid = $5032 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 = $3700

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

And, Time (t) = 6 years

Thus, Amount (A)

= $3700 + ($3700 × 6% × 6)

= $3700 + ($3700 ×⁶/₁₀₀ × 6)

= $3700 + (^{3700 × 6 × 6}/₁₀₀)

= $3700 + (^{22200 × 6}/₁₀₀)

= $3700 + (¹³³²⁰⁰/₁₀₀)

= $3700 + $1332 = $5032

Thus, Amount (A) to be paid = $5032 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 $3700, the simple interest in 1 year

= ⁶/₁₀₀ × 3700

= ^{6 × 3700}/₁₀₀

= ²²²⁰⁰/₁₀₀ = $222

Thus, simple interest for 1 year = $222

Therefore, simple interest for 6 years

= Simple interest for 1 year × 6

= $222 × 6 = $1332

Thus, Simple Interest (SI) = $1332

Calculation of Amount

Amount = Principal + Interest

Thus, Amount = $3700 + $1332

= $5032

Thus, Amount to be paid = $5032 Answer

Similar Questions

(1) Calculate the amount due after 9 years if Michael borrowed a sum of $5300 at a rate of 8% simple interest.

(2) Joseph took a loan of $5400 at the rate of 7% simple interest per annum. If he paid an amount of $8424 to clear the loan, then find the time period of the loan.

(3) If Nancy paid $4648 to settle his loan which he had taken 4 years before at a simple interest of 3%, then find the loan taken.

(4) What amount does William have to pay after 6 years if he takes a loan of $3500 at 6% simple interest?

(5) If Richard borrowed $3600 from a bank at a rate of 3% simple interest per annum then find the amount to be paid after 2 years.

(6) Calculate the amount due after 10 years if Robert borrowed a sum of $5100 at a rate of 4% simple interest.

(7) Find the amount to be paid if Robert borrowed a sum of $5100 at 10% simple interest for 8 years.

(8) Calculate the amount due after 9 years if Sarah borrowed a sum of $5850 at a rate of 2% simple interest.

(9) What amount will be due after 2 years if Donald borrowed a sum of $3750 at a 6% simple interest?

(10) Calculate the amount due if Michael borrowed a sum of $3300 at 10% simple interest for 3 years.