Simple Interest
Math MCQs

Question :    What amount does Jennifer have to pay after 6 years if he takes a loan of $3250 at 10% simple interest?

Correct Answer  $5200

Solution & Explanation

Solution

Given,

Principal (P) = $3250

Rate of Simple Interest (SI) = 10%

Time (t) = 6 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) = $3250 × 10% × 6

= $3250 ×¹⁰/₁₀₀ × 6

= ^{3250 × 10 × 6}/₁₀₀

= ^{32500 × 6}/₁₀₀

= ¹⁹⁵⁰⁰⁰/₁₀₀

= $1950

Thus, Simple Interest = $1950

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 = $3250 + $1950

= $5200

Thus, Amount to be paid = $5200 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 = $3250

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

And, Time (t) = 6 years

Thus, Amount (A)

= $3250 + ($3250 × 10% × 6)

= $3250 + ($3250 ×¹⁰/₁₀₀ × 6)

= $3250 + (^{3250 × 10 × 6}/₁₀₀)

= $3250 + (^{32500 × 6}/₁₀₀)

= $3250 + (¹⁹⁵⁰⁰⁰/₁₀₀)

= $3250 + $1950 = $5200

Thus, Amount (A) to be paid = $5200 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 $3250, the simple interest in 1 year

= ¹⁰/₁₀₀ × 3250

= ^{10 × 3250}/₁₀₀

= ³²⁵⁰⁰/₁₀₀ = $325

Thus, simple interest for 1 year = $325

Therefore, simple interest for 6 years

= Simple interest for 1 year × 6

= $325 × 6 = $1950

Thus, Simple Interest (SI) = $1950

Calculation of Amount

Amount = Principal + Interest

Thus, Amount = $3250 + $1950

= $5200

Thus, Amount to be paid = $5200 Answer

Similar Questions

(1) Steven had to pay $5014 in order to furnish the loan taken 3 years before. If the rate of simple interest was 3% then find the sum borrowed.

(2) Find the amount to be paid if Christopher borrowed a sum of $6000 at 6% simple interest for 8 years.

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

(4) Find the amount to be paid if William borrowed a sum of $5500 at 7% simple interest for 7 years.

(5) Calculate the amount due if Mary borrowed a sum of $3050 at 5% simple interest for 4 years.

(6) Calculate the amount due if Charles borrowed a sum of $3900 at 5% simple interest for 3 years.

(7) Jennifer took a loan of $4500 at the rate of 10% simple interest per annum. If he paid an amount of $7650 to clear the loan, then find the time period of the loan.

(8) Calculate the amount due if Karen borrowed a sum of $3950 at 7% simple interest for 4 years.

(9) Find the amount to be paid if Jennifer borrowed a sum of $5250 at 3% simple interest for 7 years.

(10) William took a loan of $5000 at the rate of 6% simple interest per annum. If he paid an amount of $7400 to clear the loan, then find the time period of the loan.