Simple Interest
MCQs Math


Question:     Find the amount to be paid if Richard borrowed a sum of $5600 at 3% simple interest for 8 years.


Correct Answer  $6944

Solution And Explanation

Solution

Given,

Principal (P) = $5600

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) = $5600 × 3% × 8

= $5600 ×3/100 × 8

= 5600 × 3 × 8/100

= 16800 × 8/100

= 134400/100

= $1344

Thus, Simple Interest = $1344

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 = $5600 + $1344

= $6944

Thus, Amount to be paid = $6944 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 = $5600

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

And, Time (t) = 8 years

Thus, Amount (A)

= $5600 + ($5600 × 3% × 8)

= $5600 + ($5600 ×3/100 × 8)

= $5600 + (5600 × 3 × 8/100)

= $5600 + (16800 × 8/100)

= $5600 + (134400/100)

= $5600 + $1344 = $6944

Thus, Amount (A) to be paid = $6944 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 $5600, the simple interest in 1 year

= 3/100 × 5600

= 3 × 5600/100

= 16800/100 = $168

Thus, simple interest for 1 year = $168

Therefore, simple interest for 8 years

= Simple interest for 1 year × 8

= $168 × 8 = $1344

Thus, Simple Interest (SI) = $1344

Calculation of Amount

Amount = Principal + Interest

Thus, Amount = $5600 + $1344

= $6944

Thus, Amount to be paid = $6944 Answer


Similar Questions

(1) Calculate the amount due after 9 years if Christopher borrowed a sum of $6000 at a rate of 6% simple interest.

(2) What amount does David have to pay after 5 years if he takes a loan of $3400 at 5% simple interest?

(3) What amount will be due after 2 years if Paul borrowed a sum of $3850 at a 10% simple interest?

(4) If William paid $3920 to settle his loan which he had taken 4 years before at a simple interest of 3%, then find the loan taken.

(5) If Karen paid $4424 to settle his loan which he had taken 4 years before at a simple interest of 3%, then find the loan taken.

(6) Joseph took a loan of $5400 at the rate of 9% simple interest per annum. If he paid an amount of $8316 to clear the loan, then find the time period of the loan.

(7) Donald took a loan of $7000 at the rate of 10% simple interest per annum. If he paid an amount of $11900 to clear the loan, then find the time period of the loan.

(8) Anthony took a loan of $6600 at the rate of 9% simple interest per annum. If he paid an amount of $11946 to clear the loan, then find the time period of the loan.

(9) Find the amount to be paid if Mary borrowed a sum of $5050 at 9% simple interest for 8 years.

(10) How much loan did Susan borrow 5 years ago at a rate of simple interest 4% per annum, if he paid $6780 to clear it?


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