Simple Interest
MCQs Math


Question:     Find the amount to be paid if Jennifer borrowed a sum of $5250 at 4% simple interest for 7 years.


Correct Answer  $6720

Solution And Explanation

Solution

Given,

Principal (P) = $5250

Rate of Simple Interest (SI) = 4%

Time (t) = 7 years

Thus, Amount (A) = ?

The Rate of Interest is always calculated per annum, i.e. per year.

Thus, here 4% simple interest means, Rate of Simple Interest (SI) is 4% 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) = $5250 × 4% × 7

= $5250 ×4/100 × 7

= 5250 × 4 × 7/100

= 21000 × 7/100

= 147000/100

= $1470

Thus, Simple Interest = $1470

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 = $5250 + $1470

= $6720

Thus, Amount to be paid = $6720 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 = $5250

Rate of Simple Interest (SI) or (R) = 4%

And, Time (t) = 7 years

Thus, Amount (A)

= $5250 + ($5250 × 4% × 7)

= $5250 + ($5250 ×4/100 × 7)

= $5250 + (5250 × 4 × 7/100)

= $5250 + (21000 × 7/100)

= $5250 + (147000/100)

= $5250 + $1470 = $6720

Thus, Amount (A) to be paid = $6720 Answer

Method (3) Unitary Method

Calculation of Amount using Unitary Method

Calculation of Interest using Unitary Method

Here, given Rate of Simple Interest = 4%

This, means, $4 per $100 per year

∵ For $100, the simple interest for 1 year = $4

∴ For $1, the simple interest for 1 year = 4/100

∴ For $5250, the simple interest in 1 year

= 4/100 × 5250

= 4 × 5250/100

= 21000/100 = $210

Thus, simple interest for 1 year = $210

Therefore, simple interest for 7 years

= Simple interest for 1 year × 7

= $210 × 7 = $1470

Thus, Simple Interest (SI) = $1470

Calculation of Amount

Amount = Principal + Interest

Thus, Amount = $5250 + $1470

= $6720

Thus, Amount to be paid = $6720 Answer


Similar Questions

(1) Calculate the amount due if James borrowed a sum of $3000 at 3% simple interest for 4 years.

(2) What amount does Christopher have to pay after 5 years if he takes a loan of $4000 at 5% simple interest?

(3) If Thomas borrowed $3800 from a bank at a rate of 3% simple interest per annum then find the amount to be paid after 2 years.

(4) Karen took a loan of $5900 at the rate of 7% simple interest per annum. If he paid an amount of $9204 to clear the loan, then find the time period of the loan.

(5) If Emily paid $5510 to settle his loan which he had taken 4 years before at a simple interest of 4%, then find the loan taken.

(6) 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.

(7) What amount does Thomas have to pay after 5 years if he takes a loan of $3800 at 8% simple interest?

(8) Andrew had to pay $5088 in order to furnish the loan taken 3 years before. If the rate of simple interest was 2% then find the sum borrowed.

(9) Matthew took a loan of $6400 at the rate of 9% simple interest per annum. If he paid an amount of $9856 to clear the loan, then find the time period of the loan.

(10) Find the amount to be paid if Richard borrowed a sum of $5600 at 10% simple interest for 7 years.


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