Simple Interest
MCQs Math


Question:     Calculate the amount due after 9 years if Thomas borrowed a sum of $5800 at a rate of 3% simple interest.


Correct Answer  $7366

Solution And Explanation

Solution

Given,

Principal (P) = $5800

Rate of Simple Interest (SI) = 3%

Time (t) = 9 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) = $5800 × 3% × 9

= $5800 ×3/100 × 9

= 5800 × 3 × 9/100

= 17400 × 9/100

= 156600/100

= $1566

Thus, Simple Interest = $1566

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 = $5800 + $1566

= $7366

Thus, Amount to be paid = $7366 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 = $5800

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

And, Time (t) = 9 years

Thus, Amount (A)

= $5800 + ($5800 × 3% × 9)

= $5800 + ($5800 ×3/100 × 9)

= $5800 + (5800 × 3 × 9/100)

= $5800 + (17400 × 9/100)

= $5800 + (156600/100)

= $5800 + $1566 = $7366

Thus, Amount (A) to be paid = $7366 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 $5800, the simple interest in 1 year

= 3/100 × 5800

= 3 × 5800/100

= 17400/100 = $174

Thus, simple interest for 1 year = $174

Therefore, simple interest for 9 years

= Simple interest for 1 year × 9

= $174 × 9 = $1566

Thus, Simple Interest (SI) = $1566

Calculation of Amount

Amount = Principal + Interest

Thus, Amount = $5800 + $1566

= $7366

Thus, Amount to be paid = $7366 Answer


Similar Questions

(1) What amount will be due after 2 years if Donald borrowed a sum of $3750 at a 8% simple interest?

(2) If Sandra paid $5340 to settle his loan which he had taken 4 years before at a simple interest of 5%, then find the loan taken.

(3) What amount does Karen have to pay after 5 years if he takes a loan of $3950 at 8% simple interest?

(4) Susan took a loan of $5300 at the rate of 8% simple interest per annum. If he paid an amount of $7844 to clear the loan, then find the time period of the loan.

(5) Calculate the amount due after 9 years if Linda borrowed a sum of $5350 at a rate of 2% simple interest.

(6) If Karen paid $4740 to settle his loan which he had taken 4 years before at a simple interest of 5%, then find the loan taken.

(7) Patricia took a loan of $4300 at the rate of 9% simple interest per annum. If he paid an amount of $7396 to clear the loan, then find the time period of the loan.

(8) Calculate the amount due if William borrowed a sum of $3500 at 2% simple interest for 3 years.

(9) Find the amount to be paid if Thomas borrowed a sum of $5800 at 7% simple interest for 8 years.

(10) Betty took a loan of $6500 at the rate of 8% simple interest per annum. If he paid an amount of $11180 to clear the loan, then find the time period of the loan.


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