Simple Interest
Math MCQs

Question :    What amount will be due after 2 years if Anthony borrowed a sum of $3650 at a 6% simple interest?

Correct Answer  $4088

Solution & Explanation

Solution

Given,

Principal (P) = $3650

Rate of Simple Interest (SI) = 6%

Time (t) = 2 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) = $3650 × 6% × 2

= $3650 ×⁶/₁₀₀ × 2

= ^{3650 × 6 × 2}/₁₀₀

= ^{21900 × 2}/₁₀₀

= ⁴³⁸⁰⁰/₁₀₀

= $438

Thus, Simple Interest = $438

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 + $438

= $4088

Thus, Amount to be paid = $4088 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) = 6%

And, Time (t) = 2 years

Thus, Amount (A)

= $3650 + ($3650 × 6% × 2)

= $3650 + ($3650 ×⁶/₁₀₀ × 2)

= $3650 + (^{3650 × 6 × 2}/₁₀₀)

= $3650 + (^{21900 × 2}/₁₀₀)

= $3650 + (⁴³⁸⁰⁰/₁₀₀)

= $3650 + $438 = $4088

Thus, Amount (A) to be paid = $4088 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 $3650, the simple interest in 1 year

= ⁶/₁₀₀ × 3650

= ^{6 × 3650}/₁₀₀

= ²¹⁹⁰⁰/₁₀₀ = $219

Thus, simple interest for 1 year = $219

Therefore, simple interest for 2 years

= Simple interest for 1 year × 2

= $219 × 2 = $438

Thus, Simple Interest (SI) = $438

Calculation of Amount

Amount = Principal + Interest

Thus, Amount = $3650 + $438

= $4088

Thus, Amount to be paid = $4088 Answer

Similar Questions

(1) In how much time a principal of $3050 will amount to $3507.5 at a simple interest of 5% per annum?

(2) Calculate the amount due after 9 years if Linda borrowed a sum of $5350 at a rate of 7% simple interest.

(3) Patricia took a loan of $4300 at the rate of 7% simple interest per annum. If he paid an amount of $7009 to clear the loan, then find the time period of the loan.

(4) What amount will be due after 2 years if Michael borrowed a sum of $3150 at a 9% simple interest?

(5) Find the amount to be paid if Mary borrowed a sum of $5050 at 10% simple interest for 7 years.

(6) How much loan did Sarah borrow 5 years ago at a rate of simple interest 3% per annum, if he paid $6727.5 to clear it?

(7) What amount does Linda have to pay after 5 years if he takes a loan of $3350 at 5% simple interest?

(8) In how much time a principal of $3150 will amount to $3780 at a simple interest of 5% per annum?

(9) Calculate the amount due if James borrowed a sum of $3000 at 3% simple interest for 3 years.

(10) If Mark paid $5104 to settle his loan which he had taken 4 years before at a simple interest of 4%, then find the loan taken.