Simple Interest
Math MCQs

Question :    Find the amount to be paid if Joseph borrowed a sum of $5700 at 10% simple interest for 8 years.

Correct Answer  $10260

Solution & Explanation

Solution

Given,

Principal (P) = $5700

Rate of Simple Interest (SI) = 10%

Time (t) = 8 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) = $5700 × 10% × 8

= $5700 ×¹⁰/₁₀₀ × 8

= ^{5700 × 10 × 8}/₁₀₀

= ^{57000 × 8}/₁₀₀

= ⁴⁵⁶⁰⁰⁰/₁₀₀

= $4560

Thus, Simple Interest = $4560

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 + $4560

= $10260

Thus, Amount to be paid = $10260 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) = 10%

And, Time (t) = 8 years

Thus, Amount (A)

= $5700 + ($5700 × 10% × 8)

= $5700 + ($5700 ×¹⁰/₁₀₀ × 8)

= $5700 + (^{5700 × 10 × 8}/₁₀₀)

= $5700 + (^{57000 × 8}/₁₀₀)

= $5700 + (⁴⁵⁶⁰⁰⁰/₁₀₀)

= $5700 + $4560 = $10260

Thus, Amount (A) to be paid = $10260 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 $5700, the simple interest in 1 year

= ¹⁰/₁₀₀ × 5700

= ^{10 × 5700}/₁₀₀

= ⁵⁷⁰⁰⁰/₁₀₀ = $570

Thus, simple interest for 1 year = $570

Therefore, simple interest for 8 years

= Simple interest for 1 year × 8

= $570 × 8 = $4560

Thus, Simple Interest (SI) = $4560

Calculation of Amount

Amount = Principal + Interest

Thus, Amount = $5700 + $4560

= $10260

Thus, Amount to be paid = $10260 Answer

Similar Questions

(1) Find the amount to be paid if Patricia borrowed a sum of $5150 at 4% simple interest for 8 years.

(2) Calculate the amount due if Richard borrowed a sum of $3600 at 2% simple interest for 4 years.

(3) What amount does Charles have to pay after 5 years if he takes a loan of $3900 at 4% simple interest?

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

(5) Calculate the amount due if Robert borrowed a sum of $3100 at 8% simple interest for 3 years.

(6) What amount does Mary have to pay after 6 years if he takes a loan of $3050 at 7% simple interest?

(7) Steven had to pay $4876 in order to furnish the loan taken 3 years before. If the rate of simple interest was 2% then find the sum borrowed.

(8) If Matthew paid $4704 to settle his loan which he had taken 4 years before at a simple interest of 3%, then find the loan taken.

(9) Calculate the amount due after 9 years if Joseph borrowed a sum of $5700 at a rate of 8% simple interest.

(10) Calculate the amount due if Patricia borrowed a sum of $3150 at 10% simple interest for 3 years.