Simple Interest
Math MCQs

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

Correct Answer  $4588

Solution & Explanation

Solution

Given,

Principal (P) = $3700

Rate of Simple Interest (SI) = 6%

Time (t) = 4 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% × 4

= $3700 ×⁶/₁₀₀ × 4

= ^{3700 × 6 × 4}/₁₀₀

= ^{22200 × 4}/₁₀₀

= ⁸⁸⁸⁰⁰/₁₀₀

= $888

Thus, Simple Interest = $888

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 + $888

= $4588

Thus, Amount to be paid = $4588 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) = 4 years

Thus, Amount (A)

= $3700 + ($3700 × 6% × 4)

= $3700 + ($3700 ×⁶/₁₀₀ × 4)

= $3700 + (^{3700 × 6 × 4}/₁₀₀)

= $3700 + (^{22200 × 4}/₁₀₀)

= $3700 + (⁸⁸⁸⁰⁰/₁₀₀)

= $3700 + $888 = $4588

Thus, Amount (A) to be paid = $4588 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 4 years

= Simple interest for 1 year × 4

= $222 × 4 = $888

Thus, Simple Interest (SI) = $888

Calculation of Amount

Amount = Principal + Interest

Thus, Amount = $3700 + $888

= $4588

Thus, Amount to be paid = $4588 Answer

Similar Questions

(1) Find the amount to be paid if Jennifer borrowed a sum of $5250 at 2% simple interest for 7 years.

(2) Calculate the amount due if Michael borrowed a sum of $3300 at 4% simple interest for 4 years.

(3) Find the amount to be paid if Jessica borrowed a sum of $5750 at 3% simple interest for 8 years.

(4) Robert had to pay $3565 in order to furnish the loan taken 3 years before. If the rate of simple interest was 5% then find the sum borrowed.

(5) Jennifer took a loan of $4500 at the rate of 9% simple interest per annum. If he paid an amount of $7335 to clear the loan, then find the time period of the loan.

(6) How much loan did Ryan borrow 5 years ago at a rate of simple interest 3% per annum, if he paid $9085 to clear it?

(7) Matthew took a loan of $6400 at the rate of 9% simple interest per annum. If he paid an amount of $11584 to clear the loan, then find the time period of the loan.

(8) Jessica took a loan of $5500 at the rate of 8% simple interest per annum. If he paid an amount of $8580 to clear the loan, then find the time period of the loan.

(9) Find the amount to be paid if Linda borrowed a sum of $5350 at 9% simple interest for 8 years.

(10) Calculate the amount due if John borrowed a sum of $3200 at 3% simple interest for 3 years.