Simple Interest
MCQs Math


Question:     Find the amount to be paid if Christopher borrowed a sum of $6000 at 2% simple interest for 7 years.


Correct Answer  $6840

Solution And Explanation

Solution

Given,

Principal (P) = $6000

Rate of Simple Interest (SI) = 2%

Time (t) = 7 years

Thus, Amount (A) = ?

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

Thus, here 2% simple interest means, Rate of Simple Interest (SI) is 2% 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) = $6000 × 2% × 7

= $6000 ×2/100 × 7

= 6000 × 2 × 7/100

= 12000 × 7/100

= 84000/100

= $840

Thus, Simple Interest = $840

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 = $6000 + $840

= $6840

Thus, Amount to be paid = $6840 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 = $6000

Rate of Simple Interest (SI) or (R) = 2%

And, Time (t) = 7 years

Thus, Amount (A)

= $6000 + ($6000 × 2% × 7)

= $6000 + ($6000 ×2/100 × 7)

= $6000 + (6000 × 2 × 7/100)

= $6000 + (12000 × 7/100)

= $6000 + (84000/100)

= $6000 + $840 = $6840

Thus, Amount (A) to be paid = $6840 Answer

Method (3) Unitary Method

Calculation of Amount using Unitary Method

Calculation of Interest using Unitary Method

Here, given Rate of Simple Interest = 2%

This, means, $2 per $100 per year

∵ For $100, the simple interest for 1 year = $2

∴ For $1, the simple interest for 1 year = 2/100

∴ For $6000, the simple interest in 1 year

= 2/100 × 6000

= 2 × 6000/100

= 12000/100 = $120

Thus, simple interest for 1 year = $120

Therefore, simple interest for 7 years

= Simple interest for 1 year × 7

= $120 × 7 = $840

Thus, Simple Interest (SI) = $840

Calculation of Amount

Amount = Principal + Interest

Thus, Amount = $6000 + $840

= $6840

Thus, Amount to be paid = $6840 Answer


Similar Questions

(1) Find the amount to be paid if David borrowed a sum of $5400 at 10% simple interest for 7 years.

(2) How much loan did Cynthia borrow 5 years ago at a rate of simple interest 2% per annum, if he paid $8745 to clear it?

(3) Nancy had to pay $4648 in order to furnish the loan taken 3 years before. If the rate of simple interest was 4% then find the sum borrowed.

(4) Find the amount to be paid if James borrowed a sum of $5000 at 7% simple interest for 8 years.

(5) What amount does Patricia have to pay after 5 years if he takes a loan of $3150 at 9% simple interest?

(6) Calculate the amount due after 9 years if Karen borrowed a sum of $5950 at a rate of 4% simple interest.

(7) Calculate the amount due after 10 years if Linda borrowed a sum of $5350 at a rate of 8% simple interest.

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

(9) Lisa took a loan of $6100 at the rate of 10% simple interest per annum. If he paid an amount of $12200 to clear the loan, then find the time period of the loan.

(10) How much loan did Robert borrow 5 years ago at a rate of simple interest 3% per annum, if he paid $5865 to clear it?


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