Simple Interest
Math MCQs

Question :    What amount does Linda have to pay after 5 years if he takes a loan of $3350 at 10% simple interest?

Correct Answer  $5025

Solution & Explanation

Solution

Given,

Principal (P) = $3350

Rate of Simple Interest (SI) = 10%

Time (t) = 5 years

Thus, Amount (A) = ?

The Rate of Interest is always calculated per annum, i.e. per year.

Thus, here 10% simple interest means, Rate of Simple Interest (SI) is 10% 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) = $3350 × 10% × 5

= $3350 ×¹⁰/₁₀₀ × 5

= ^{3350 × 10 × 5}/₁₀₀

= ^{33500 × 5}/₁₀₀

= ¹⁶⁷⁵⁰⁰/₁₀₀

= $1675

Thus, Simple Interest = $1675

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 = $3350 + $1675

= $5025

Thus, Amount to be paid = $5025 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 = $3350

Rate of Simple Interest (SI) or (R) = 10%

And, Time (t) = 5 years

Thus, Amount (A)

= $3350 + ($3350 × 10% × 5)

= $3350 + ($3350 ×¹⁰/₁₀₀ × 5)

= $3350 + (^{3350 × 10 × 5}/₁₀₀)

= $3350 + (^{33500 × 5}/₁₀₀)

= $3350 + (¹⁶⁷⁵⁰⁰/₁₀₀)

= $3350 + $1675 = $5025

Thus, Amount (A) to be paid = $5025 Answer

Method (3) Unitary Method

Calculation of Amount using Unitary Method

Calculation of Interest using Unitary Method

Here, given Rate of Simple Interest = 10%

This, means, $10 per $100 per year

∵ For $100, the simple interest for 1 year = $10

∴ For $1, the simple interest for 1 year = ¹⁰/₁₀₀

∴ For $3350, the simple interest in 1 year

= ¹⁰/₁₀₀ × 3350

= ^{10 × 3350}/₁₀₀

= ³³⁵⁰⁰/₁₀₀ = $335

Thus, simple interest for 1 year = $335

Therefore, simple interest for 5 years

= Simple interest for 1 year × 5

= $335 × 5 = $1675

Thus, Simple Interest (SI) = $1675

Calculation of Amount

Amount = Principal + Interest

Thus, Amount = $3350 + $1675

= $5025

Thus, Amount to be paid = $5025 Answer

Similar Questions

(1) How much loan did Mark borrow 5 years ago at a rate of simple interest 4% per annum, if he paid $7680 to clear it?

(2) Find the amount to be paid if Christopher borrowed a sum of $6000 at 7% simple interest for 7 years.

(3) Michael took a loan of $4600 at the rate of 9% simple interest per annum. If he paid an amount of $7084 to clear the loan, then find the time period of the loan.

(4) What amount does Mary have to pay after 5 years if he takes a loan of $3050 at 10% simple interest?

(5) If Joshua paid $5684 to settle his loan which he had taken 4 years before at a simple interest of 4%, then find the loan taken.

(6) Calculate the amount due if Thomas borrowed a sum of $3800 at 4% simple interest for 3 years.

(7) What amount does Sarah have to pay after 6 years if he takes a loan of $3850 at 8% simple interest?

(8) How much loan did Steven borrow 5 years ago at a rate of simple interest 2% per annum, if he paid $7260 to clear it?

(9) John took a loan of $4400 at the rate of 10% simple interest per annum. If he paid an amount of $7040 to clear the loan, then find the time period of the loan.

(10) Jessica had to pay $4312.5 in order to furnish the loan taken 3 years before. If the rate of simple interest was 5% then find the sum borrowed.