Simple Interest
MCQs Math


Question:     Find the amount to be paid if Sarah borrowed a sum of $5850 at 3% simple interest for 8 years.


Correct Answer  $7254

Solution And Explanation

Solution

Given,

Principal (P) = $5850

Rate of Simple Interest (SI) = 3%

Time (t) = 8 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) = $5850 × 3% × 8

= $5850 ×3/100 × 8

= 5850 × 3 × 8/100

= 17550 × 8/100

= 140400/100

= $1404

Thus, Simple Interest = $1404

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 = $5850 + $1404

= $7254

Thus, Amount to be paid = $7254 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 = $5850

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

And, Time (t) = 8 years

Thus, Amount (A)

= $5850 + ($5850 × 3% × 8)

= $5850 + ($5850 ×3/100 × 8)

= $5850 + (5850 × 3 × 8/100)

= $5850 + (17550 × 8/100)

= $5850 + (140400/100)

= $5850 + $1404 = $7254

Thus, Amount (A) to be paid = $7254 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 $5850, the simple interest in 1 year

= 3/100 × 5850

= 3 × 5850/100

= 17550/100 = $175.5

Thus, simple interest for 1 year = $175.5

Therefore, simple interest for 8 years

= Simple interest for 1 year × 8

= $175.5 × 8 = $1404

Thus, Simple Interest (SI) = $1404

Calculation of Amount

Amount = Principal + Interest

Thus, Amount = $5850 + $1404

= $7254

Thus, Amount to be paid = $7254 Answer


Similar Questions

(1) Find the amount to be paid if Robert borrowed a sum of $5100 at 7% simple interest for 8 years.

(2) In how much time a principal of $3000 will amount to $3180 at a simple interest of 2% per annum?

(3) In how much time a principal of $3050 will amount to $3355 at a simple interest of 5% per annum?

(4) If Joseph paid $4292 to settle his loan which he had taken 4 years before at a simple interest of 4%, then find the loan taken.

(5) Patricia took a loan of $4300 at the rate of 7% simple interest per annum. If he paid an amount of $7009 to clear the loan, then find the time period of the loan.

(6) How much loan did William borrow 5 years ago at a rate of simple interest 2% per annum, if he paid $6050 to clear it?

(7) How much loan did Joshua borrow 5 years ago at a rate of simple interest 3% per annum, if he paid $7935 to clear it?

(8) Calculate the amount due after 9 years if Barbara borrowed a sum of $5550 at a rate of 5% simple interest.

(9) Donald took a loan of $7000 at the rate of 9% simple interest per annum. If he paid an amount of $13300 to clear the loan, then find the time period of the loan.

(10) Calculate the amount due after 9 years if David borrowed a sum of $5400 at a rate of 6% simple interest.


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