Simple Interest
Math MCQs

Question :  ( 1 of 10 )  What amount does Susan have to pay after 5 years if he takes a loan of $3650 at 6% simple interest?

Correct Answer  $4745

Solution & Explanation

Solution

Given,

Principal (P) = $3650

Rate of Simple Interest (SI) = 6%

Time (t) = 5 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% × 5

= $3650 ×⁶/₁₀₀ × 5

= ^{3650 × 6 × 5}/₁₀₀

= ^{21900 × 5}/₁₀₀

= ¹⁰⁹⁵⁰⁰/₁₀₀

= $1095

Thus, Simple Interest = $1095

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 + $1095

= $4745

Thus, Amount to be paid = $4745 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) = 5 years

Thus, Amount (A)

= $3650 + ($3650 × 6% × 5)

= $3650 + ($3650 ×⁶/₁₀₀ × 5)

= $3650 + (^{3650 × 6 × 5}/₁₀₀)

= $3650 + (^{21900 × 5}/₁₀₀)

= $3650 + (¹⁰⁹⁵⁰⁰/₁₀₀)

= $3650 + $1095 = $4745

Thus, Amount (A) to be paid = $4745 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 5 years

= Simple interest for 1 year × 5

= $219 × 5 = $1095

Thus, Simple Interest (SI) = $1095

Calculation of Amount

Amount = Principal + Interest

Thus, Amount = $3650 + $1095

= $4745

Thus, Amount to be paid = $4745 Answer

Similar Questions

(1) What amount will be due after 2 years if Joseph borrowed a sum of $3350 at a 6% simple interest?

(2) Sarah took a loan of $5700 at the rate of 8% simple interest per annum. If he paid an amount of $10260 to clear the loan, then find the time period of the loan.

(3) Calculate the amount due if Jessica borrowed a sum of $3750 at 5% simple interest for 4 years.

(4) John took a loan of $4400 at the rate of 7% simple interest per annum. If he paid an amount of $6864 to clear the loan, then find the time period of the loan.

(5) Find the amount to be paid if Karen borrowed a sum of $5950 at 6% simple interest for 7 years.

(6) If Steven paid $5152 to settle his loan which he had taken 4 years before at a simple interest of 3%, then find the loan taken.

(7) What amount will be due after 2 years if Robert borrowed a sum of $3050 at a 9% simple interest?

(8) Susan took a loan of $5300 at the rate of 8% simple interest per annum. If he paid an amount of $8692 to clear the loan, then find the time period of the loan.

(9) If Susan paid $3942 to settle his loan which he had taken 4 years before at a simple interest of 2%, then find the loan taken.

(10) How much loan did Nancy borrow 5 years ago at a rate of simple interest 5% per annum, if he paid $7687.5 to clear it?