Simple Interest
Math MCQs

Question :    Calculate the amount due after 10 years if Joseph borrowed a sum of $5700 at a rate of 3% simple interest.

Correct Answer  $7410

Solution & Explanation

Solution

Given,

Principal (P) = $5700

Rate of Simple Interest (SI) = 3%

Time (t) = 10 years

Thus, Amount (A) = ?

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

Thus, here 3% simple interest means, Rate of Simple Interest (SI) is 3% 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) = $5700 × 3% × 10

= $5700 ׳/₁₀₀ × 10

= ^{5700 × 3 × 10}/₁₀₀

= ^{17100 × 10}/₁₀₀

= ¹⁷¹⁰⁰⁰/₁₀₀

= $1710

Thus, Simple Interest = $1710

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 = $5700 + $1710

= $7410

Thus, Amount to be paid = $7410 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 = $5700

Rate of Simple Interest (SI) or (R) = 3%

And, Time (t) = 10 years

Thus, Amount (A)

= $5700 + ($5700 × 3% × 10)

= $5700 + ($5700 ׳/₁₀₀ × 10)

= $5700 + (^{5700 × 3 × 10}/₁₀₀)

= $5700 + (^{17100 × 10}/₁₀₀)

= $5700 + (¹⁷¹⁰⁰⁰/₁₀₀)

= $5700 + $1710 = $7410

Thus, Amount (A) to be paid = $7410 Answer

Method (3) Unitary Method

Calculation of Amount using Unitary Method

Calculation of Interest using Unitary Method

Here, given Rate of Simple Interest = 3%

This, means, $3 per $100 per year

∵ For $100, the simple interest for 1 year = $3

∴ For $1, the simple interest for 1 year = ³/₁₀₀

∴ For $5700, the simple interest in 1 year

= ³/₁₀₀ × 5700

= ^{3 × 5700}/₁₀₀

= ¹⁷¹⁰⁰/₁₀₀ = $171

Thus, simple interest for 1 year = $171

Therefore, simple interest for 10 years

= Simple interest for 1 year × 10

= $171 × 10 = $1710

Thus, Simple Interest (SI) = $1710

Calculation of Amount

Amount = Principal + Interest

Thus, Amount = $5700 + $1710

= $7410

Thus, Amount to be paid = $7410 Answer

Similar Questions

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

(2) What amount will be due after 2 years if Daniel borrowed a sum of $3550 at a 8% simple interest?

(3) Elizabeth had to pay $3657 in order to furnish the loan taken 3 years before. If the rate of simple interest was 2% then find the sum borrowed.

(4) Find the amount to be paid if Jessica borrowed a sum of $5750 at 7% simple interest for 8 years.

(5) If Sandra paid $5162 to settle his loan which he had taken 4 years before at a simple interest of 4%, then find the loan taken.

(6) What amount does Mary have to pay after 5 years if he takes a loan of $3050 at 9% simple interest?

(7) Elizabeth took a loan of $4900 at the rate of 10% simple interest per annum. If he paid an amount of $7840 to clear the loan, then find the time period of the loan.

(8) How much loan did Sandra borrow 5 years ago at a rate of simple interest 3% per annum, if he paid $7417.5 to clear it?

(9) Calculate the amount due if Karen borrowed a sum of $3950 at 5% simple interest for 3 years.

(10) Karen took a loan of $5900 at the rate of 6% simple interest per annum. If he paid an amount of $9086 to clear the loan, then find the time period of the loan.