Simple Interest
Math MCQs

Question :    Find the amount to be paid if Elizabeth borrowed a sum of $5450 at 6% simple interest for 8 years.

Correct Answer  $8066

Solution & Explanation

Solution

Given,

Principal (P) = $5450

Rate of Simple Interest (SI) = 6%

Time (t) = 8 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) = $5450 × 6% × 8

= $5450 ×⁶/₁₀₀ × 8

= ^{5450 × 6 × 8}/₁₀₀

= ^{32700 × 8}/₁₀₀

= ²⁶¹⁶⁰⁰/₁₀₀

= $2616

Thus, Simple Interest = $2616

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 = $5450 + $2616

= $8066

Thus, Amount to be paid = $8066 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 = $5450

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

And, Time (t) = 8 years

Thus, Amount (A)

= $5450 + ($5450 × 6% × 8)

= $5450 + ($5450 ×⁶/₁₀₀ × 8)

= $5450 + (^{5450 × 6 × 8}/₁₀₀)

= $5450 + (^{32700 × 8}/₁₀₀)

= $5450 + (²⁶¹⁶⁰⁰/₁₀₀)

= $5450 + $2616 = $8066

Thus, Amount (A) to be paid = $8066 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 $5450, the simple interest in 1 year

= ⁶/₁₀₀ × 5450

= ^{6 × 5450}/₁₀₀

= ³²⁷⁰⁰/₁₀₀ = $327

Thus, simple interest for 1 year = $327

Therefore, simple interest for 8 years

= Simple interest for 1 year × 8

= $327 × 8 = $2616

Thus, Simple Interest (SI) = $2616

Calculation of Amount

Amount = Principal + Interest

Thus, Amount = $5450 + $2616

= $8066

Thus, Amount to be paid = $8066 Answer

Similar Questions

(1) If Kenneth paid $5800 to settle his loan which he had taken 4 years before at a simple interest of 4%, then find the loan taken.

(2) Calculate the amount due if Susan borrowed a sum of $3650 at 9% simple interest for 3 years.

(3) Michael took a loan of $4600 at the rate of 6% simple interest per annum. If he paid an amount of $6256 to clear the loan, then find the time period of the loan.

(4) Calculate the amount due if Jennifer borrowed a sum of $3250 at 6% simple interest for 3 years.

(5) What amount does Elizabeth have to pay after 6 years if he takes a loan of $3450 at 7% simple interest?

(6) What amount does Joseph have to pay after 6 years if he takes a loan of $3700 at 3% simple interest?

(7) What amount will be due after 2 years if Kenneth borrowed a sum of $4000 at a 9% simple interest?

(8) Calculate the amount due after 10 years if Elizabeth borrowed a sum of $5450 at a rate of 5% simple interest.

(9) Find the amount to be paid if John borrowed a sum of $5200 at 8% simple interest for 7 years.

(10) What amount does Robert have to pay after 6 years if he takes a loan of $3100 at 8% simple interest?