Simple Interest
MCQs Math


Question:     Calculate the amount due after 10 years if William borrowed a sum of $5500 at a rate of 3% simple interest.


Correct Answer  $7150

Solution And Explanation

Solution

Given,

Principal (P) = $5500

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) = $5500 × 3% × 10

= $5500 ×3/100 × 10

= 5500 × 3 × 10/100

= 16500 × 10/100

= 165000/100

= $1650

Thus, Simple Interest = $1650

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 = $5500 + $1650

= $7150

Thus, Amount to be paid = $7150 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 = $5500

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

And, Time (t) = 10 years

Thus, Amount (A)

= $5500 + ($5500 × 3% × 10)

= $5500 + ($5500 ×3/100 × 10)

= $5500 + (5500 × 3 × 10/100)

= $5500 + (16500 × 10/100)

= $5500 + (165000/100)

= $5500 + $1650 = $7150

Thus, Amount (A) to be paid = $7150 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 $5500, the simple interest in 1 year

= 3/100 × 5500

= 3 × 5500/100

= 16500/100 = $165

Thus, simple interest for 1 year = $165

Therefore, simple interest for 10 years

= Simple interest for 1 year × 10

= $165 × 10 = $1650

Thus, Simple Interest (SI) = $1650

Calculation of Amount

Amount = Principal + Interest

Thus, Amount = $5500 + $1650

= $7150

Thus, Amount to be paid = $7150 Answer


Similar Questions

(1) Calculate the amount due if Charles borrowed a sum of $3900 at 7% simple interest for 3 years.

(2) If John paid $3456 to settle his loan which he had taken 4 years before at a simple interest of 2%, then find the loan taken.

(3) Patricia took a loan of $4300 at the rate of 9% simple interest per annum. If he paid an amount of $8170 to clear the loan, then find the time period of the loan.

(4) Calculate the amount due if David borrowed a sum of $3400 at 5% simple interest for 4 years.

(5) What amount will be due after 2 years if Steven borrowed a sum of $3800 at a 9% simple interest?

(6) In how much time a principal of $3050 will amount to $3660 at a simple interest of 5% per annum?

(7) Richard took a loan of $5200 at the rate of 9% simple interest per annum. If he paid an amount of $8476 to clear the loan, then find the time period of the loan.

(8) Calculate the amount due after 9 years if Susan borrowed a sum of $5650 at a rate of 10% simple interest.

(9) Calculate the amount due after 9 years if James borrowed a sum of $5000 at a rate of 4% simple interest.

(10) If Robert paid $3348 to settle his loan which he had taken 4 years before at a simple interest of 2%, then find the loan taken.


NCERT Solution and CBSE Notes for class twelve, eleventh, tenth, ninth, seventh, sixth, fifth, fourth and General Math for competitive Exams. ©