Simple Interest
MCQs Math


Question:     What amount does Richard have to pay after 6 years if he takes a loan of $3600 at 6% simple interest?


Correct Answer  $4896

Solution And Explanation

Solution

Given,

Principal (P) = $3600

Rate of Simple Interest (SI) = 6%

Time (t) = 6 years

Thus, Amount (A) = ?

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

Thus, here 6% simple interest means, Rate of Simple Interest (SI) is 6% 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) = $3600 × 6% × 6

= $3600 ×6/100 × 6

= 3600 × 6 × 6/100

= 21600 × 6/100

= 129600/100

= $1296

Thus, Simple Interest = $1296

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 = $3600 + $1296

= $4896

Thus, Amount to be paid = $4896 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 = $3600

Rate of Simple Interest (SI) or (R) = 6%

And, Time (t) = 6 years

Thus, Amount (A)

= $3600 + ($3600 × 6% × 6)

= $3600 + ($3600 ×6/100 × 6)

= $3600 + (3600 × 6 × 6/100)

= $3600 + (21600 × 6/100)

= $3600 + (129600/100)

= $3600 + $1296 = $4896

Thus, Amount (A) to be paid = $4896 Answer

Method (3) Unitary Method

Calculation of Amount using Unitary Method

Calculation of Interest using Unitary Method

Here, given Rate of Simple Interest = 6%

This, means, $6 per $100 per year

∵ For $100, the simple interest for 1 year = $6

∴ For $1, the simple interest for 1 year = 6/100

∴ For $3600, the simple interest in 1 year

= 6/100 × 3600

= 6 × 3600/100

= 21600/100 = $216

Thus, simple interest for 1 year = $216

Therefore, simple interest for 6 years

= Simple interest for 1 year × 6

= $216 × 6 = $1296

Thus, Simple Interest (SI) = $1296

Calculation of Amount

Amount = Principal + Interest

Thus, Amount = $3600 + $1296

= $4896

Thus, Amount to be paid = $4896 Answer


Similar Questions

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

(2) Find the amount to be paid if Susan borrowed a sum of $5650 at 8% simple interest for 8 years.

(3) Sarah had to pay $4312 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 Mary borrowed a sum of $5050 at 6% simple interest for 7 years.

(5) Calculate the amount due after 10 years if Michael borrowed a sum of $5300 at a rate of 5% simple interest.

(6) How much loan did Sharon borrow 5 years ago at a rate of simple interest 2% per annum, if he paid $8525 to clear it?

(7) Find the amount to be paid if John borrowed a sum of $5200 at 6% simple interest for 7 years.

(8) Calculate the amount due after 10 years if Barbara borrowed a sum of $5550 at a rate of 3% simple interest.

(9) Calculate the amount due after 10 years if Linda borrowed a sum of $5350 at a rate of 6% simple interest.

(10) How much loan did Donald borrow 5 years ago at a rate of simple interest 5% per annum, if he paid $8125 to clear it?


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