Simple Interest
Math MCQs

Question :    Find the amount to be paid if Richard borrowed a sum of $5600 at 6% simple interest for 7 years.

Correct Answer  $7952

Solution & Explanation

Solution

Given,

Principal (P) = $5600

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) = $5600 × 6% × 7

= $5600 ×⁶/₁₀₀ × 7

= ^{5600 × 6 × 7}/₁₀₀

= ^{33600 × 7}/₁₀₀

= ²³⁵²⁰⁰/₁₀₀

= $2352

Thus, Simple Interest = $2352

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 = $5600 + $2352

= $7952

Thus, Amount to be paid = $7952 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 = $5600

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

And, Time (t) = 7 years

Thus, Amount (A)

= $5600 + ($5600 × 6% × 7)

= $5600 + ($5600 ×⁶/₁₀₀ × 7)

= $5600 + (^{5600 × 6 × 7}/₁₀₀)

= $5600 + (^{33600 × 7}/₁₀₀)

= $5600 + (²³⁵²⁰⁰/₁₀₀)

= $5600 + $2352 = $7952

Thus, Amount (A) to be paid = $7952 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 $5600, the simple interest in 1 year

= ⁶/₁₀₀ × 5600

= ^{6 × 5600}/₁₀₀

= ³³⁶⁰⁰/₁₀₀ = $336

Thus, simple interest for 1 year = $336

Therefore, simple interest for 7 years

= Simple interest for 1 year × 7

= $336 × 7 = $2352

Thus, Simple Interest (SI) = $2352

Calculation of Amount

Amount = Principal + Interest

Thus, Amount = $5600 + $2352

= $7952

Thus, Amount to be paid = $7952 Answer

Similar Questions

(1) Find the amount to be paid if William borrowed a sum of $5500 at 7% simple interest for 7 years.

(2) Thomas had to pay $4256 in order to furnish the loan taken 3 years before. If the rate of simple interest was 4% then find the sum borrowed.

(3) What amount will be due after 2 years if Charles borrowed a sum of $3450 at a 8% simple interest?

(4) Sandra took a loan of $6900 at the rate of 10% simple interest per annum. If he paid an amount of $13110 to clear the loan, then find the time period of the loan.

(5) If Sarah borrowed $3850 from a bank at a rate of 3% simple interest per annum then find the amount to be paid after 2 years.

(6) What amount does John have to pay after 5 years if he takes a loan of $3200 at 2% simple interest?

(7) Karen took a loan of $5900 at the rate of 7% simple interest per annum. If he paid an amount of $10030 to clear the loan, then find the time period of the loan.

(8) Calculate the amount due after 9 years if Linda borrowed a sum of $5350 at a rate of 9% simple interest.

(9) What amount does Richard have to pay after 6 years if he takes a loan of $3600 at 6% simple interest?

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